JP2015210306A - Optical connector and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical connector that can be produced with a minimal increase in manufacturing cost, and to provide a manufacturing method therefor.SOLUTION: An optical connector 1A comprises optical fibers 3A and a ferrule 5A for fixing the optical fibers 3A, the ferrule 5A having an end face 5a to be coupled with another optical component such as an optical connector 2, another end face 5b different from the end face 5a, and a holding section formed from the end face 5a through to the end face 5b, where the optical fibers 3A have lenses 4 protruding from the end face 5b and are held by the holding section.

Description

  The present invention relates to an optical connector and a method for manufacturing the optical connector.

  Patent Document 1 below describes an optical connector in which a part of a holder of an optical connector and a lens array are integrally formed. In the optical connector described in Patent Document 1, the space between the end face of the optical fiber and the lens array is filled with an adhesive. When this adhesive is cured at a temperature higher than the upper limit of the temperature at the time of use or storage of the optical connector, the interface between the adhesive and the optical connector is separated, or fine bubbles are formed in the adhesive. An optical connector that is suppressed from occurring can be obtained.

US Pat. No. 7,510,337

  In an information processing device in a data center or an HPC (High Performance Computer) that performs advanced information processing, an optical fiber for transmitting signals is optically connected between devices or within a device (between multiple boards included in an information processing device). Has been. As one of optical connection methods, for example, as described in Patent Document 1, there is a method using an optical connector in which a lens array is attached to the tip of a multi-core optical fiber. In the optical connection using such an optical connector, the beams expanded by the respective lenses provided in the lens array are optically connected, so that the optical fiber is not misaligned and the configuration of the optical connector does not become large. Optical connection can be realized at low cost.

  In the optical connection using the optical connector described above, since the ferrule and the lens array are assembled, it has been difficult to achieve further significant cost reduction. Also, in general, a refractive index matching material that matches the refractive index or an adhesive in which the refractive index is matched with both the optical fiber and the lens array to reduce reflection loss between the optical fiber and the lens array. Material is inserted. For this reason, the process of inserting a refractive index matching material or an adhesive material contributes to an increase in assembly cost of the optical connector. Furthermore, in the process of inserting a refractive index matching material or an adhesive material, if bubbles are mixed between the optical fiber and the lens array, a connection loss in the optical connection occurs, so a highly accurate optical connection can be realized. It becomes difficult.

  The present invention has been made in view of such problems, and an object thereof is to provide an optical connector and an optical connector manufacturing method capable of suppressing an increase in manufacturing cost.

  In order to solve the above-described problem, an optical connector according to one aspect of the present invention includes an optical fiber and a ferrule that fixes the optical fiber, and the ferrule includes a first end surface connected to another optical component, and , A second end face different from the first end face, and a holding part formed from the first end face to the second end face, and the optical fiber has a lens part protruding from the first end face and holds Held by the part.

  An optical connector manufacturing method according to an aspect of the present invention includes an optical fiber and a ferrule to which the optical fiber is fixed, and the ferrule has a first end surface connected to another optical component, and a first end surface. A method of manufacturing an optical connector having a second end surface different from the step of preparing a ferrule having a holding portion formed from the first end surface to the second end surface, and disposing the optical fiber in the holding portion. A step of forming a lens portion by melting the tip portion of the optical fiber protruding from the first end surface, a step of pulling back the optical fiber so that the lens portion protrudes from the first end surface, and the optical fiber as a holding portion. Adhering and fixing.

  According to the optical connector and the optical connector manufacturing method of the present invention, an increase in the manufacturing cost of the optical connector can be suppressed.

FIG. 1 is a top view showing a schematic configuration of the optical connector according to the first embodiment. FIG. 2 is a cross-sectional view showing a II-II cross section of the optical connector shown in FIG. FIG. 3 is a perspective view showing a schematic configuration of a ferrule included in the optical connector according to the first embodiment. FIG. 4 is a flowchart showing the main steps included in the method of manufacturing an optical connector according to the first embodiment. FIGS. 5A to 5D are diagrams showing main steps included in the method of manufacturing the optical connector according to the first embodiment. FIG. 6 is a top view illustrating a schematic configuration of an optical connector according to a modification of the first embodiment. 7 is a cross-sectional view showing a VII-VII cross section of the optical connector shown in FIG. FIG. 8 is a top view showing a schematic configuration of the optical connector according to the second embodiment. FIG. 9 is a cross-sectional view showing a IX-IX cross section of the optical connector shown in FIG. FIG. 10A to FIG. 10D are diagrams showing main steps included in the method of manufacturing an optical connector according to the second embodiment. FIG. 11 is a top view illustrating a schematic configuration of an optical connector according to a modification of the second embodiment. 12 is a cross-sectional view showing an XII-XII cross section of the optical connector shown in FIG. FIG. 13 is a top view showing a schematic configuration of the optical connector according to the third embodiment. FIG. 14 is a diagram for explaining the optical optimum design distance. FIG. 15 is a top view illustrating a schematic configuration of an optical connector according to a modification of the third embodiment. FIG. 16 is a top view illustrating a schematic configuration of the optical connector according to the fourth embodiment. FIG. 17A to FIG. 17D are diagrams showing main steps included in the method of manufacturing an optical connector according to the fourth embodiment. FIG. 18 is a top view illustrating a schematic configuration of an optical connector according to a modification of the fourth embodiment. FIG. 19 is a top view illustrating a schematic configuration of a ferrule included in an optical connector according to a modification of the fourth embodiment.

[Description of Embodiment of Present Invention]
First, the contents of the embodiment of the present invention will be listed and described. An optical connector according to one aspect of the present invention includes: (1) an optical fiber; and a ferrule that fixes the optical fiber. The ferrule includes a first end surface connected to another optical component, and a first end surface. The second end surface is different from the first end surface and the holding portion is formed from the first end surface to the second end surface. The optical fiber has a lens portion protruding from the first end surface, and is held by the holding portion.

  In the above optical connector, the optical fiber has a lens portion. The lens portion is fixed by holding the optical fiber by the holding member. Therefore, the lens portion can be fixed to the ferrule without assembling the ferrule and a member such as a lens array. In addition, for example, when the ferrule is optically connected to another optical component, the beams expanded by the lens unit are optically connected, so that even if the optical fiber is misaligned, connection loss is less likely to occur. In addition, since the configuration of the optical connector does not become large, it is possible to realize optical connection at low cost. And in an optical connector, since it becomes unnecessary to provide a lens member as another member, the number of parts for performing optical connection can be decreased. Furthermore, since the optical connector can be assembled without inserting a refractive index matching material or an adhesive material, it is possible to suppress the occurrence of connection loss due to mixing of bubbles. Therefore, since it can manufacture efficiently, suppressing generation | occurrence | production of a connection loss, the raise of manufacturing cost can be suppressed.

  (2) The holding part is an optical fiber hole into which the optical fiber is inserted or an optical fiber groove that accommodates the optical fiber, and the maximum diameter of the lens part is the diameter of the optical fiber hole in the first end face or the first diameter. It may be larger than the width of the opening of the optical fiber groove at the end face. In the optical connector obtained by such a configuration, the optical fiber is less likely to drop off from the ferrule. For this reason, since it can manufacture efficiently, the raise of manufacturing cost is suppressed.

  (3) The optical fiber may have a plastic layer. The optical connector obtained by such a configuration can be easily processed. Moreover, since a lens part can be formed from a plastic layer, the increase in manufacturing cost can be suppressed.

  (4) The optical fiber and the ferrule may be bonded and fixed at a position different from a region on the surface of the lens unit through which light incident on the lens unit or light emitted from the lens unit passes. In the optical connector obtained by such a configuration, the light incident on the lens portion or the light emitted from the lens portion is not obstructed by the ferrule or the like, so that the signal light is hardly blocked and the occurrence of connection loss is suppressed. For example, the optical fiber hole may function as an introduction hole for introducing an adhesive. The lens portion may be substantially spherical.

  (5) The lens portion may be fixed in contact with the first end surface. In the optical connector obtained by such a configuration, the axial deviation of the optical fiber is reduced. In this case, the lens unit may be bonded and fixed at a position in contact with the first end surface. Further, the lens portion may be brought into contact with the first end surface by applying tension to the optical fiber. If comprised in this way, since an optical fiber is fixed, applying a tension | tensile_strength, the end surface position of an optical fiber is arrange | equalized. Furthermore, since the center axis of the optical fiber is disposed along the center axis of the optical fiber hole or the center line extending in the extending direction of the optical fiber groove, the axial shift of the optical fiber can be suppressed.

  (6) The ferrule may have a first fitting hole for fitting to be connected to another optical component on the first end surface. In the optical connector obtained by such a configuration, connection with other optical components becomes easy. Therefore, optical connection using the optical connector can be easily performed.

  Further, (7) the ferrule may further include a fitting pin that fits into the first fitting hole in order to be connected to another optical component. In the optical connector obtained by such a configuration, connection with other optical components becomes easy. Therefore, optical connection using the optical connector can be easily performed.

  (8) The fitting pin includes a first narrow diameter portion accommodated in the first fitting hole, a second small diameter portion accommodated in a second fitting hole included in another optical component, and a first There may be provided a large-diameter portion that connects the small-diameter portion and the second small-diameter portion and defines a separation distance between the other optical component and the first end surface. In the optical connector obtained by such a configuration, the separation distance between the first end surface of the ferrule and the other optical component is defined by the large diameter portion, so that the separation distance for realizing optical connection with high efficiency is provided. It can be set easily.

  Further, (9) the ferrule has a concave window hole formed in the third surface intersecting the first end surface and the second end surface, and the holding portion penetrates between the first end surface and the window hole. May be. In the optical connector obtained by such a configuration, for example, an optical fiber arranged in a ferrule can be fixed by pouring resin through a window hole. For this reason, the optical fiber can be easily bonded and fixed.

  (10) The optical fiber has a coated part and an uncoated part, and the boundary between the coated part and the uncoated part is located in the window hole. Good. In the optical connector obtained by such a configuration, it is possible to prevent the uncovered portion of the optical fiber from being damaged by the optical fiber groove.

  An optical connector manufacturing method according to an aspect of the present invention includes (11) an optical fiber and a ferrule to which the optical fiber is fixed. The ferrule includes a first end surface connected to another optical component; A method of manufacturing an optical connector having a second end surface different from the end surface, the step of preparing a ferrule having a holding portion formed from the first end surface to the second end surface, and arranging the optical fiber in the holding portion A step of forming a lens portion by melting the tip portion of the optical fiber protruding from the first end surface, a step of pulling back the optical fiber so that the lens portion protrudes from the first end surface, and a holding portion of the optical fiber. Adhering and fixing to.

  In the above optical connector manufacturing method, the lens portion is formed by melt processing. The optical fiber is bonded and fixed while the lens portion is in contact with the first end surface. Therefore, the lens portion can be fixed to the ferrule without assembling the ferrule and a member such as a lens array. In addition, for example, when the ferrule is optically connected to another optical component, the beams expanded by the lens unit are optically connected, so that even if the optical fiber is misaligned, connection loss is less likely to occur. In addition, since the configuration of the optical connector does not become large, it is possible to realize optical connection at low cost. Since the optical connector does not need to be provided with a lens member as a separate member, the number of components for optical connection can be reduced. Furthermore, since the optical connector can be assembled without inserting a refractive index matching material or an adhesive material, it is possible to suppress the occurrence of connection loss due to mixing of bubbles. Therefore, since it can manufacture efficiently, suppressing generation | occurrence | production of a connection loss, the raise of manufacturing cost can be suppressed.

  Further, (12) before disposing the optical fiber in the holding part, a step of removing the coating on the tip side of the optical fiber may be further included. According to the manufacturing method of the optical connector obtained by such a configuration, the outer diameter on the distal end side in the optical fiber insertion direction is thinner than the outer diameter on the rear end side. For this reason, since the portion of the optical fiber close to the lens portion can be held by the optical fiber hole having a small inner diameter, the deviation between the central axis of the optical fiber hole and the central axis of the lens portion of the optical fiber is reduced. Can do.

  Moreover, (13) After arrange | positioning an optical fiber to a holding | maintenance part, you may further include the process of removing the coating | cover at the front end side of an optical fiber. According to the manufacturing method of the optical connector obtained by such a configuration, it is suppressed that the ferrule damages the optical fiber when the optical fiber is disposed.

  In addition, (14) the holding portion is an optical fiber hole into which the optical fiber is inserted or an optical fiber groove in which the optical fiber is disposed. In the step of forming the lens portion, the maximum diameter of the lens portion to be formed is It may be larger than the diameter of the optical fiber hole at the one end face or the width of the opening of the optical fiber groove at the first end face. According to the manufacturing method of the optical connector obtained by such a configuration, the optical fiber is unlikely to fall off from the ferrule. For this reason, since it can manufacture efficiently, the raise of manufacturing cost is suppressed.

  (15) In the step of bonding and fixing the optical fiber to the holding portion, the optical fiber may be bonded and fixed to the holding portion in a state where tension is applied in a direction in which the optical fiber is pulled back. According to the optical connector manufacturing method obtained by such a configuration, the optical fiber is fixed while the lens portion is in contact with the first end surface, so that the end surface position of the optical fiber is aligned. Further, when the holding portion where the optical fiber is disposed is an optical fiber hole, the lens portion can prevent the adhesive material from protruding from the first end surface by blocking the optical fiber hole on the first end surface. . Furthermore, since the center axis of the optical fiber is arranged along the center axis of the optical fiber hole, it is possible to suppress the axial deviation of the optical fiber. Further, when the holding portion in which the optical fiber is disposed is an optical fiber groove, the optical fiber is displaced along the center line extending in the extending direction of the optical fiber groove so that the optical fiber is offset. Can be suppressed.

[Details of the embodiment of the present invention]
Specific examples of the optical connector and the optical connector manufacturing method according to the embodiment of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to the claim are included. In the following description, the same reference numerals are given to the same elements in the description of the drawings, and redundant descriptions are omitted.

(First embodiment)
An optical connector 1A according to the first embodiment will be described with reference to FIG. 1, FIG. 2, and FIG. FIG. 1 is a top view showing a schematic configuration of an optical connector 1A according to the present embodiment. FIG. 2 is a cross-sectional view showing a II-II cross section of the optical connector 1A shown in FIG. FIG. 3 is a perspective view showing a schematic configuration of a ferrule 5A included in the optical connector 1A according to the first embodiment. For easy understanding, an XYZ orthogonal coordinate system is shown in the figure. In the following description, the side in contact with other optical components is referred to as the distal end side, and the side from which the optical fiber is drawn out is referred to as the proximal end side. The X axis extends from the proximal end side toward the distal end side.

  As shown in FIGS. 1 and 2, the optical connector 1 </ b> A includes N optical fibers 3 </ b> A (N is an integer of 1 or more, N = 4 in this embodiment), and a ferrule 5 </ b> A. The optical connector 1A optically and mechanically connects the optical fiber 3A and other optical components. In the optical connector 1A, a ferrule 5A is attached to one end side of the optical fiber 3A. The optical fiber 3A includes a strand 31 having a core 31a and a clad 31b outside the core 31a, and a coating 32 that covers the strand 31. The optical fiber 3A has a plastic layer. The clad 31b may be formed of, for example, a plastic material. The optical fiber 3A has a coated portion 3a and an uncoated portion 3b. The covered portion 3 a is a portion where the wire 31 is covered with the covering 32, and the uncovered portion 3 b is a portion where the strand 31 is not covered with the covering 32. In the present embodiment, a multimode fiber having a numerical aperture (NA) of 0.2 can be exemplified as the optical fiber 3A, and 50 μm can be exemplified as the core diameter of the core 31a. Further, in the optical fiber 3A, the diameter of the covered portion 3a can be exemplified as 250 μm, and the diameter of the uncoated portion 3b can be exemplified as 125 μm. The optical fiber 3A may be a ribbon fiber.

  The ferrule 5A is a member for fixing the optical fiber 3A, and is, for example, a resin optical connector ferrule. As further shown in FIG. 3, the ferrule 5A has an end surface 5a (first end surface) that abuts another optical member to be connected and an end surface 5b (second end surface) different from the end surface 5a. Yes. The end surface 5a and the end surface 5b extend along the YZ plane and face each other. The ferrule 5A has a surface 5c that intersects the end surface 5a and the end surface 5b and extends along the XY plane. In the ferrule 5A, a notch 7 is formed in a region where the end surface 5b and the surface 5c intersect. The notch portion 7 functions as an injection portion for injecting an adhesive B for fixing the optical fiber 3A to the ferrule 5A.

  In the ferrule 5A, N optical fiber holes 9A (holding portions) for inserting a plurality of optical fibers 3A are formed. Each of the N optical fiber holes 9A extends along the X-axis direction. In the present embodiment, the distance along the Y-axis direction of the four optical fiber holes 9A is 250 μm, and the diameter of each of the optical fiber holes 9A can be exemplified as 127 μm. The optical fiber hole 9A penetrates between the end surface 5a and the cutout portion 7. Uncoated portions 3b of the N optical fibers 3A are respectively inserted into the N optical fiber holes 9A. The notch 7 is provided with N optical fiber grooves 11 that serve as a guide when the optical fiber 3A is inserted into the optical fiber hole 9A from the base end side of the N optical fiber holes 9A. The optical fiber hole 9A and the optical fiber groove 11 function as a holding portion that holds the optical fiber 3A.

  The optical fiber 3A has a substantially spherical lens portion 4 (see FIGS. 1 and 2). The curvature radius of the lens part 4 can illustrate about 0.24 mm. In the optical connector 1A, the lens part 4 protrudes from the end surface 5a. The lens unit 4 is fixed in contact with the end surface 5a. As shown in FIG. 2, the end surface 5a side surface of the lens unit 4 and the end surface 5a are in contact with each other. That is, the region where the optical fiber 3A and the ferrule 5A are bonded and fixed is different from the region on the surface of the lens unit 4 through which the light incident on the lens unit 4 or the light emitted from the lens unit 4 passes.

(Production method)
Here, with reference to FIG.4 and FIG.5, the manufacturing method of 1 A of optical connectors is demonstrated. FIG. 4 is a flowchart showing main steps included in the method of manufacturing the optical connector 1A according to the first embodiment. FIG. 5A to FIG. 5D are diagrams showing main steps included in the method of manufacturing the optical connector 1A.

  First, in step S10, an optical fiber 3A and a ferrule 5A to which the optical fiber 3A is fixed are prepared (see FIG. 5A). An optical fiber hole 9A is formed in the ferrule 5A from the end surface 5a to the notch 7. The optical fiber 3A has an uncoated portion 3b at the tip of the optical fiber 3A.

Next, in step S12, the optical fibers 3A are inserted into the optical fiber holes 9A, respectively. At this time, the uncoated portion 3b of the optical fiber 3A passes through the optical fiber hole 9A (see FIG. 2). Then, the tip end portion of the optical fiber 3A is projected from the end face 5a, and the tip portion is melted by, for example, irradiating the tip portion with a laser beam by a CO ₂ laser (see FIG. 5B). The melt processing may be, for example, a YAG laser. In this case, a harmonic laser may be used. Further, the curvature of the lens unit 4 formed at the tip may be adjusted by the laser power or the focal position. Note that, as described above, the melting process may be performed by irradiating the tip of the optical fiber 3A with laser light, and by irradiating the intermediate part of the optical fiber 3A with laser light, the optical fiber 3A. You may process it, cutting the said fusion | melting location, fuse | melting. In step S12, the clad formed from the plastic material is melt-processed, and the lens portion 4 is formed at the tip of the optical fiber 3A. (See (c) in FIG. 5).

  Next, in step S14, the optical fiber 3A is pulled back to the side opposite to the insertion direction of the optical fiber 3A. At this time, the uncoated portion 3b is pulled back into the ferrule 5A, and the state in which the lens portion 4 protrudes from the end surface 5a is maintained. Moreover, the lens part 4 protrudes from the ferrule 5A so that the area | region through which the light which injects into the lens part 4 or the light radiate | emitted from the lens part 4 passes may not be blocked | interrupted.

  In step S16, the optical fiber 3A is bonded and fixed to the optical fiber hole 9A (see FIG. 5D). At this time, the adhesive B is applied to the notch 7 and cured. Thereby, the lens part 4 is fixed in the state contact | abutted to the end surface 5a. In step S <b> 16, the optical fiber 3 </ b> A and the ferrule 5 </ b> A are bonded and fixed at a position different from a region on the surface of the lens unit 4 through which light incident on the lens unit 4 or light emitted from the lens unit 4 passes. In step S16, for example, the fiber is bonded in a state where a tension of 10 g is applied, so that the lifting of the lens unit 4 from the end surface 5a of the ferrule 5A is suppressed, and the optical fiber 3A or the lens due to the force of pulling back is suppressed. Damage to the portion 4 can be prevented. The optical connector 1A is obtained through the above steps S10 to S16.

(Modification of the first embodiment)
Here, with reference to FIG.6 and FIG.7, the optical connector 1B which concerns on the modification of 1st embodiment is demonstrated. FIG. 6 is a top view showing a schematic configuration of an optical connector 1B according to a modification of the embodiment. FIG. 7 is a cross-sectional view showing a VII-VII cross section of the optical connector 1B shown in FIG.

  As shown in FIGS. 6 and 7, a concave window hole 8 is formed in the surface 5c of the ferrule 5B. The opening of the window hole 8 is formed to have a longitudinal direction along the Y-axis direction. The optical fiber hole 9 </ b> A passes through the end face 5 a and the window hole 8, and also passes through the window hole 8 and the notch portion 7. The window hole 8 functions as a hole for injecting an adhesive B for fixing the optical fiber 3A to the ferrule 5B. In a process corresponding to the above-described process S14, the adhesive B is applied to the notch 7 and the window hole 8 and cured. Thereby, the optical fiber 3 </ b> A is fixed in the window hole 8 together with the notch 7. Therefore, since the optical fiber 3A is bonded and fixed at a position close to the lens unit 4, the positioning accuracy can be improved. The configuration of ferrule 5B other than the above is the same as that of ferrule 5A.

  As described above, according to the optical connectors 1A and 1B of the first embodiment, since the optical fiber 3A has the lens portion 4, the lens portion 4 is fixed by holding the optical fiber 3A by the optical fiber hole 9A. Therefore, for example, the lens portion 4 can be fixed to the ferrules 5A and 5B without assembling the ferrules 5A and 5B and a member such as a lens array. Further, for example, when the ferrules 5A and 5B are optically connected to other optical components, the beams expanded by the lens unit 4 are optically connected to each other, so that connection loss occurs even when the optical fiber 3A is misaligned. It becomes difficult. In addition, since the configuration of the optical connectors 1A and 1B does not become large, it is possible to realize optical connection at low cost. And since optical connector 1A and 1B do not need to provide the lens part 4 as another member, the number of parts for performing an optical connection can be decreased. Furthermore, since the optical connectors 1A and 1B can be assembled without inserting a refractive index matching material or an adhesive, it is possible to suppress the occurrence of connection loss due to mixing of bubbles. Therefore, since it can manufacture efficiently, suppressing generation | occurrence | production of a connection loss, the raise of manufacturing cost can be suppressed.

  Furthermore, since the maximum diameter of the lens portion 4 is larger than the diameter of the optical fiber hole 9A in the end face 5a, the optical fiber 3A is less likely to drop off from the ferrules 5A and 5B. For this reason, since it can manufacture efficiently, the raise of manufacturing cost is suppressed. Further, since the optical fiber 3A has a plastic layer, the lens portion 4 can be easily processed from the plastic layer. Thereby, the increase in manufacturing cost can be suppressed.

  The optical fiber 3A and the ferrules 5A and 5B are bonded and fixed at predetermined positions. This predetermined position is a position different from a region on the surface of the lens unit 4 through which light incident on the lens unit 4 or light emitted from the lens unit 4 passes. For this reason, since the light which injects into the lens part 4, or the light radiate | emitted from the lens part 4 is not inhibited by a ferrule etc., it becomes difficult to block signal light at the time of optical connection, and generation | occurrence | production of a connection loss is suppressed.

  Further, since the lens portion 4 is fixed in contact with the end surface 5a, the axial displacement of the optical fiber 3A in the optical connectors 1A and 1B is reduced. Further, since the optical fiber 3A is fixed while applying tension, the end face positions of the optical fiber 3A are aligned. Since the center axis of the optical fiber 3A is arranged along the center axis of the optical fiber hole 9A or the center line extending in the extending direction of the optical fiber groove 11, the axial deviation of the optical fiber 3A can be suppressed.

  Further, since the optical fiber hole 9A and the window hole 8 penetrating therethrough are provided, for example, by pouring resin through the window hole 8, the optical fiber 3A held by the ferrules 5A and 5B can be fixed. For this reason, the adhesive fixing of the optical fiber 3A can be easily performed.

(Second embodiment)
The optical connector 1C according to the second embodiment will be described with reference to FIG. 8, FIG. 9, and FIG. The optical connector 1C according to the second embodiment is the same as the optical connector 1A according to the first embodiment except for the configuration of the optical fiber 3B and the ferrule 5C. Hereinafter, overlapping description with the first embodiment will be omitted, and differences will be mainly described.

  FIG. 8 is a top view showing a schematic configuration of the optical connector 1C according to the second embodiment. FIG. 9 is a cross-sectional view showing a IX-IX cross section of the optical connector 1 </ b> C shown in FIG. 8. FIG. 10A to FIG. 10D are diagrams showing main steps included in the method of manufacturing the optical connector 1C.

  As shown in FIGS. 8 and 9, in the optical connector 1C, a ferrule 5C is attached to one end side of the optical fiber 3B. The optical fiber 3B has a covered portion 3a. In the ferrule 5C, N optical fiber holes 9B are formed. The inner diameter of the optical fiber hole 9B is equal to the diameter of the covered portion 3a. The other configuration of the optical fiber hole 9B is the same as that of the optical fiber hole 9A. A covered portion 3a of the optical fiber 3B is inserted into the optical fiber hole 9B. For example, the interval along the Y-axis direction of the optical fiber hole 9B is 500 μm, and the diameter of the optical fiber hole 9B is 255 μm. The optical fiber 3B has a substantially spherical lens portion 4. The diameter of the lens portion 4 protruding from the end surface 5a is larger than the opening width of the optical fiber groove 11 in the end surface 5a. The configuration of ferrule 5C other than the above is the same as that of ferrule 5A.

  Moreover, the manufacturing method of the optical connector 1C according to the present embodiment includes the following main steps. First, in a step corresponding to step S10, an optical fiber 3B and a ferrule 5C to which the optical fiber 3B is fixed are prepared (see FIG. 10A).

  Next, in a step corresponding to step S12, the optical fibers 3B are inserted into the optical fiber holes 9B, respectively. At this time, in the optical fiber 3B, the covered portion 3a passes through the optical fiber hole 9B. Then, the lens portion 4 is formed by irradiating the tip portion of the optical fiber 3B with laser light and melting the plastic layer at the tip portion (see FIGS. 10B and 10C). ). In addition, the curvature radius of the lens part 4 can illustrate about 0.27 mm.

  Next, in a step corresponding to step S14, the optical fiber 3B is pulled back so that the lens portion 4 protrudes from the end face 5a. At this time, the optical fiber 3B is pulled back so that the covered portion 3a of the optical fiber 3B is disposed over the entire optical fiber hole 9B and the optical fiber groove 11. In a step corresponding to step S16, the optical fiber 3B is bonded and fixed to the optical fiber hole 9B (see FIG. 10D). At this time, the adhesive B is applied to the notch 7 and cured. Thereby, the lens part 4 is fixed in the state contact | abutted to the end surface 5a.

(Modification of the second embodiment)
Here, with reference to FIG.11 and FIG.12, optical connector 1D which concerns on the modification of 2nd embodiment is demonstrated. FIG. 11 is a top view showing a schematic configuration of an optical connector 1D according to a modification of the embodiment. FIG. 12 is a cross-sectional view showing an XII-XII cross section of the optical connector 1D shown in FIG.

  As shown in FIGS. 11 and 12, a concave window hole 8 is formed in the surface 5c of the ferrule 5D. The optical fiber hole 9 </ b> B passes through the end face 5 a and the window hole 8, and also passes between the notch 7 and the window hole 8. The optical fiber 3A is disposed in the optical fiber hole 9B. The boundary between the coated portion 3 a and the uncoated portion 3 b of the optical fiber 3 A is located in the window hole 8. In the step corresponding to step S14 described above, the boundary between the covered portion 3a and the uncovered portion 3b is formed by applying the adhesive material B to the notch portion 7 and the window hole 8 and curing it. 8 is fixed by the adhesive B in a state of being positioned at 8. Further, since the lens unit 4 becomes a plug by fixing the lens unit 4 while being pulled back, the adhesive material B is prevented from protruding from the optical fiber hole 9B on the end face 5a side. Further, since the optical fiber 3A is bonded and fixed at a position close to the lens unit 4, the positioning accuracy can be improved. The configuration of ferrule 5D other than the above is the same as that of ferrule 5A.

  As mentioned above, according to 2nd embodiment, there can exist an effect | action and effect similar to 1st embodiment. Further, according to the modification of the second embodiment, the uncoated portion 3b of the optical fiber 3B, that is, the strand 31 of the optical fiber 3A is suppressed from being damaged by the optical fiber hole 9B and the optical fiber groove 11. Can do.

(Third embodiment)
With reference to FIG. 13, the optical connector 1E which concerns on 3rd embodiment is demonstrated. The optical connector 1E according to the third embodiment is the same as the optical connector 1A according to the first embodiment except for the configuration of the first fitting hole and the fitting pin. Hereinafter, overlapping description with the first embodiment will be omitted, and differences will be mainly described.

  FIG. 13 is a top view showing a schematic configuration of an optical connector 1E according to the third embodiment. FIG. 13A illustrates a state before the optical connector 1E is optically connected to the optical connector 2 which is another optical component, and FIG. 13B illustrates the optical connector 1E. A mode after optical connection between the optical connector 2 and the optical connector 2 is shown. The optical connector 2 includes a ferrule 21 and N optical fibers 22 attached to the ferrule 21. 13 (a) and 13 (b), the ferrule 5E has a fitting hole 13 (first fitting hole) in the end face 5a, and the ferrule 21 is fitted in the end face 21a facing the ferrule 5E. A joint hole 14 (second fitting hole) is provided. The other configuration of the ferrule 5E is the same as that of the ferrule 5A.

  The fitting pin 15 is fitted with the fitting hole 13 and the fitting hole 14. The fitting pin 15 has a small diameter portion 15a (first small diameter portion), a small diameter portion 15b (second small diameter portion), and a large diameter portion 15c. The small diameter portion 15 a is fitted in the fitting hole 13, and the small diameter portion 15 b is fitted in the fitting hole 14. The diameters of the small diameter portions 15a and 15b are equal to each other, and the diameters of the small diameter portions 15a and 15b are smaller than the diameter of the large diameter portion 15c. The diameter of the large diameter portion 15 c is smaller than the inner diameter of the fitting hole 13. The large diameter portion 15c functions as a cylindrical spacer. The length in the longitudinal direction of the large-diameter portion 15c is equal to the optically optimal design distance when the optical connector 1E provided with the fitting pin 15 and the optical connector 2 are optically connected. Note that the diameters of the small diameter portions 15a and 15b may not be equal. For example, instead of the fitting pin 15, a pin that does not change in diameter may be used. In this way, it may function as a spacer for defining the design distance described above.

  Here, the optical optimum design distance will be described with reference to FIG. FIG. 14 is a diagram for explaining the optical optimum design distance. The optical optimum design distance is such that when the optical connector 1E and the optical connector 2 are optically connected, the focal length of the lens portion 4 of the optical connector 1E and the focal length of the lens portion 4A of the optical connector 2 are substantially the same. Distance.

  In FIG. 14, a ferrule 5E included in the optical connector 1E, a lens unit 4 included in the optical fiber 3A, a ferrule 21 included in the optical connector 2, and a lens unit 4A included in the optical fiber 22 are illustrated. For example, collimated light L is emitted from the lens unit 4 in the lens unit 4 and the lens unit 4A arranged to face each other, and the light L is collected by the lens unit 4A and enters the optical fiber 22. . Further, the position W of the beam waist of the emitted light may be configured to substantially coincide with the focal position of the lens unit 4A.

  In the present embodiment, the length in the longitudinal direction of the large diameter portion 15c is equal to the design distance. As described above, the design distance is such that, with the ferrule 5E and the ferrule 21 facing each other, the optical fiber 3A held by the ferrule 5E and the optical fiber 22 held by the ferrule 21 are optimally optically connected. Distance. If comprised in this way, when the thin diameter part 15a is accommodated in the fitting hole 13, and the thin diameter part 15b is accommodated in the fitting hole 14, the large diameter part 15c is between the optical connector 2 and the end surface 5a. A separation distance can be defined.

(Modification of the third embodiment)
Here, an optical connector 1F according to a modification of the third embodiment will be described with reference to FIG. As shown in FIG. 15A, the ferrule 5 </ b> F may have a fitting hole 13. The fitting hole 13 is a hole that fits into a fitting pin 25 provided in a ferrule 21A provided in the optical connector 2A (another optical component). The pin 25 is formed in a state protruding from the end face 21a of the ferrule 21 in a direction facing the ferrule 5E. The pin 25 includes a pin 26 that fits into the fitting hole 13 on the tip side. The diameter of the pin 26 is smaller than the diameter of the pin 25. The diameter of the pin 25 is larger than the inner diameter of the fitting hole 13. The pin 26 is fitted into the fitting hole 13. The configuration of the ferrule 5F other than the above is the same as that of the ferrule 5A. When configured in this way, as shown in FIG. 15B, the optical connector 1F can be optically connected to the optical connector 2A while maintaining a separation distance for realizing optical connection with high efficiency.

  As described above, according to the optical connectors 1E and 1F of the third embodiment, the optical connectors 1E and 1F and the optical connectors 2 and 2A can be easily optically connected at the optimum optical design distance. Further, since the separation distance between the end face 5a of the ferrules 5E and 5F and the end face 21a of the ferrules 21 and 21A is respectively defined by the large diameter portion 15c and the pin 25, the separation distance for realizing optical connection with high efficiency. Can be set with a simple configuration.

(Fourth embodiment)
An optical connector 1G according to the fourth embodiment will be described with reference to FIGS. The optical connector 1G according to the fourth embodiment is the same as the optical connector 1A according to the first embodiment except for the ferrule 5G. Hereinafter, overlapping description with the first embodiment will be omitted, and differences will be mainly described.

  FIG. 16 is a top view showing a schematic configuration of an optical connector 1G according to the fourth embodiment. FIG. 17A to FIG. 17D are diagrams showing main steps included in the method of manufacturing the optical connector 1G.

  As shown in FIG. 16, in the optical connector 1G, a ferrule 5G is attached to one end side of the optical fiber 3A. In the ferrule 5G, N optical fiber grooves 11 are formed from the end surface 5a to the end surface 5b (see FIG. 17A). The optical fiber groove 11 functions as a holding unit that holds the optical fiber 3A. In the optical fiber groove 11, a covered portion 3a and an uncoated portion 3b of the optical fiber 3A are disposed. An adhesive B is provided on the optical fiber 3 </ b> A disposed in the optical fiber groove 11. The maximum value of the diameter of the lens portion 4 protruding from the end surface 5a is larger than the length of the opening width of the optical fiber groove 11 in the end surface 5a. The other configuration of the ferrule 5G is the same as that of the ferrule 5A.

  Moreover, the manufacturing method of the optical connector 1G according to the present embodiment includes the following main steps. First, in a step corresponding to step S10, an optical fiber 3A and a ferrule 5G to which the optical fiber 3A is fixed are prepared. In the ferrule 5G, as described above, the N optical fiber grooves 11 are formed from the end surface 5a to the end surface 5b (see FIGS. 17A and 17B).

  Next, in a step corresponding to step S12, the optical fibers 3A are respectively arranged in the optical fiber grooves 11 so that the tip of the optical fiber 3A protrudes from the end face 5a, and the tip of the optical fiber 3A is irradiated with laser light. And melt processed. Thereby, the lens part 4 is formed.

  Next, in a step corresponding to step S14, the optical fiber 3A is pulled back in the direction opposite to the side where the lens portion 4 is formed in the optical fiber 3A. At this time, the uncoated portion 3b is pulled back into the ferrule 5G, and the state in which the lens portion 4 protrudes from the end face 5a is maintained (see FIGS. 17 (c) and 17 (d)). . Then, in a step corresponding to step S16, the optical fiber 3A is bonded and fixed to the optical fiber groove 11. On the optical fiber 3 </ b> A disposed in the optical fiber groove 11, the adhesive material B is applied so as to cover at least a part of the optical fiber 3 </ b> A and the optical fiber groove 11. Then, the applied adhesive B is cured to fix the optical fiber 3A to the ferrule 5G. Thereby, the lens part 4 is fixed in the state contact | abutted to the end surface 5a. At this time, a fixing member such as a lid may be used instead of the adhesive B.

(Modification of the fourth embodiment)
Here, with reference to FIG.18 and FIG.19, the optical connector 1H which concerns on the modification of 4th embodiment is demonstrated. FIG. 18 is a top view showing a schematic configuration of an optical connector 1H according to a modification of the embodiment. FIG. 19 is a top view illustrating a schematic configuration of a ferrule 5H included in the optical connector 1H according to the modification of the embodiment.

  As shown in FIGS. 18 and 19, the optical fiber groove 11A formed on the surface 5c of the ferrule 5H has portions 11a and 11b having different opening widths. In other words, the opening width of the optical fiber groove 11 at the end face 5a is different from the opening width of the optical fiber groove 11 at the end face 5b. The opening width of the portion 11a of the optical fiber groove 11A is the same width as the diameter of the portion 3a covered with the optical fiber 3A, for example, 260 μm. The opening width of the portion 11b of the optical fiber groove 11A is equal to the diameter of the uncoated portion 3b of the optical fiber 3A, and is a width obtained by adding a processing tolerance value and a predetermined value to the diameter of the portion 3b. Also good. Here, the predetermined width is, for example, 1 μm. The opening width of the portion 11b is, for example, 126 μm. The other configuration of the ferrule 5H is the same as that of the ferrule 5A. If comprised in this way, since the opening width of the optical fiber groove | channel 11 near the lens part 4 becomes short, 3 A of optical fibers can be fixed easily. Further, the positioning accuracy can be improved by arranging the portion 3a of the optical fiber 3A in the optical fiber groove 11 so that the play is less than that of the portion 3b.

  As described above, according to the fourth embodiment, the optical fiber 3A is less likely to drop off from the ferrules 5G and 5H. For this reason, since it can manufacture efficiently, the raise of manufacturing cost is suppressed.

  The embodiment of the present invention has been described above. However, the ferrules 5A to 5H are not limited to those described above. For example, the ferrules 5A to 5H may be applied to an existing ferrule for performing an optical connection such as an MT ferrule.

  The melt processing conditions may be changed as appropriate depending on the material of the optical fiber. In this case, the conditions may be optimized depending on the absorption characteristics of the material with respect to the laser wavelength. Further, the resin material is easier to process with respect to laser irradiation than glass. For this reason, as the optical fiber, an optical fiber having a plastic clad or an optical fiber having a plastic layer made of a plastic material around a glass clad may be used.

  DESCRIPTION OF SYMBOLS 1A-1G ... Optical connector, 2 ... Optical connector (other optical components), 3A, 3B ... Optical fiber, 4 ... Lens part, 5A-5G ... Ferrule, 5a ... End surface (1st end surface), 5b ... End surface (1st) 2 end faces), 7 ... notch, 8 ... window hole, 9A, 9B ... optical fiber hole (holding part), 11, 11A ... optical fiber groove (holding part), 13 ... fitting hole (first fitting hole) , 14 ... fitting hole (second fitting hole), 15 ... fitting pin, 15a, 15b ... small diameter part, 15c ... large diameter part.

Claims (15)

Optical fiber,
A ferrule for fixing the optical fiber,
The ferrule has a first end face connected to another optical component, a second end face different from the first end face, and a holding portion formed from the first end face to the second end face. And
The optical fiber includes an optical connector having a lens portion protruding from the first end surface and held by the holding portion. The holding portion is an optical fiber hole into which the optical fiber is inserted, or an optical fiber groove that accommodates the optical fiber,
2. The optical connector according to claim 1, wherein a maximum diameter of the lens portion is larger than a diameter of the optical fiber hole in the first end face or a width of an opening of the optical fiber groove in the first end face.   The optical connector according to claim 1, wherein the optical fiber has a plastic layer.   The optical fiber and the ferrule are bonded and fixed at a position different from a region on the surface of the lens unit through which light incident on the lens unit or light emitted from the lens unit passes. 4. The optical connector according to any one of 3.   The optical connector according to claim 1, wherein the lens unit is fixed in contact with the first end surface.   The optical connector according to any one of claims 1 to 5, wherein the ferrule has a first fitting hole for fitting to be connected to the other optical component on the first end surface.   The optical connector according to claim 6, wherein the ferrule further includes a fitting pin that fits into the first fitting hole in order to be connected to the other optical component.   The fitting pin includes a first small diameter portion accommodated in the first fitting hole, a second small diameter portion accommodated in a second fitting hole included in the other optical component, and the first thin diameter portion. The optical connector according to claim 7, further comprising a large-diameter portion that connects a diameter portion and the second small-diameter portion and defines a separation distance between the other optical component and the first end surface. The ferrule has a concave window hole formed in a third surface intersecting the first end surface and the second end surface,
The optical connector according to any one of claims 1 to 8, wherein the holding portion penetrates between the first end surface and the window hole. The optical fiber has a coated part and the uncoated part,
The optical connector according to claim 9, wherein a boundary between the covered portion and the uncovered portion is located in the window hole. An optical connector comprising: an optical fiber; and a ferrule to which the optical fiber is fixed, wherein the ferrule has a first end surface connected to another optical component and a second end surface different from the first end surface. A method,
Preparing the ferrule having a holding portion formed from the first end surface to the second end surface;
Arranging the optical fiber in the holding portion, and forming a lens portion by melting a tip portion of the optical fiber protruding from the first end surface;
Pulling back the optical fiber so that the lens portion protrudes from the first end surface;
And a step of bonding and fixing the optical fiber to the holding portion.   The method of manufacturing an optical connector according to claim 11, further comprising a step of removing a coating on a distal end side of the optical fiber before the optical fiber is disposed on the holding portion.   The method of manufacturing an optical connector according to claim 11, further comprising a step of removing a coating on a front end side of the optical fiber after the optical fiber is disposed in the holding portion. The holding portion is an optical fiber hole into which the optical fiber is inserted or an optical fiber groove in which the optical fiber is disposed,
In the step of forming the lens portion, a maximum diameter of the lens portion to be formed is larger than a diameter of the optical fiber hole in the first end surface or a width of an opening of the optical fiber groove in the first end surface. The manufacturing method of the optical connector as described in any one of 11 to 13. The optical connector manufacturing method according to claim 14, wherein in the step of bonding and fixing the optical fiber to the holding unit, the optical fiber is bonded and fixed to the holding unit in a state where tension is applied in a direction in which the optical fiber is pulled back. Method.

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