Patent Publication Number: US-2021181431-A1

Title: Optical connecting component

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation of PCT application No. PCT/IP2019/033127, which was filed on Aug. 23, 2019 based on Japanese Patent Application No. 2018-158778 filed on Aug 27, 2018, the contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to an optical connecting component. 
     BACKGROUND ART 
     As an optical module is miniaturized, when one end portion of an optical fiber is vertically and oppositely spliced to a circuit board on which an optical element such as a light emitting element, a light receiving element, and an optical circuit is mounted, it is required to reduce a height of an optical connecting component so as to keep a height of the optical fiber from the circuit board low. In order to reduce the height of the optical connecting component, it is necessary to bend a vicinity of a tip of the optical fiber with a small radius. Therefore, Patent Literature 1 discloses an optical path conversion member in which a plurality of aligned positioning grooves are formed on an upper side surface of a base circuit board having a curved tip surface that smoothly continues from a flat upper surface, and a lid member having a surface along the upper side surface of the base circuit board is provided for pressing the optical fiber housed in the positioning groove of the base circuit board. Patent Literature 2 discloses an optical connector in which the optical fiber is curved by forming a curved hole in a connector body and by inserting and fixing the optical fiber in the hole. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: IP-A-2008-52028 
     Patent Literature 2: JP-A-2007-156006 
     SUMMARY OF INVENTION 
     An optical connecting component according to one aspect of the present disclosure includes: an optical fiber; a first fixing member to which one end portion of the optical fiber is fixed; and a second fixing member including a bendable middle bone (backbone), a grip portion for griping the first fixing member on one end side of the middle bone, and an optical fiber fixing portion for fixing the optical fiber to the middle bone on the other end side of the middle bone. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1A  is a front view illustrating an example of an optical fiber provided in an optical connecting component of the present disclosure. 
         FIG. 1B  is a side view illustrating the optical fiber of  FIG. 1A . 
         FIG. 2A  is a front view illustrating an example of a first fixing member provided in the optical connecting component of the present disclosure in a state where the optical fiber is fixed thereto. 
         FIG. 2B  is a plan view illustrating the first fixing member of  FIG. 2A  in the state where the optical fiber is fixed thereto. 
         FIG. 2C  is a front view illustrating another example of the first fixing member provided in the optical connecting component of the present disclosure in a state where the optical fiber is fixed thereto. 
         FIG. 2D  is a plan view illustrating another example of the first fixing member of  FIG. 2C  in a state where the optical fiber is fixed thereto. 
         FIG. 3A  is a perspective view illustrating an example of a second fixing member of the optical connecting component of the present disclosure. 
         FIG. 3B  is a front view of the second fixing member illustrated in  FIG. 3A . 
         FIG. 3C  is a side view of the second fixing member illustrated in  FIG. 3A . 
         FIG. 4A  is a cross-sectional view illustrating an example in which the first fixing member is mounted on the second fixing member of  FIG. 3A  in a state where the second fixing member is not bent. 
         FIG. 4B  is a cross-sectional view illustrating an example in which the first fixing member is mounted on the second fixing member of  FIG. 3A  in a state where the second fixing member is bent. 
         FIG. 5  is a perspective view illustrating another example of the second fixing member of the optical connecting component of the present disclosure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Technical Problem 
     The optical path conversion member disclosed in Patent Literature 1 or the optical connector disclosed in Patent Literature 2 is required to include a circuit board having a predetermined curved surface or a connector body having a curved hole in order to bend the optical fiber to a desired radius and angle, and is required to change the circuit board and the connector body when changing a curvature of the optical fiber. The present disclosure provides an optical connecting component capable of bending and holding an optical fiber with any curvature without requiring a circuit board having a predetermined curved surface or a connector member having a curved hole. 
     Description of Embodiments of the Present Disclosure 
     First, embodiments of the present disclosure will be listed and described. 
     (1) An optical connecting component according to one aspect of the present disclosure includes: an optical fiber; a first fixing member to which one end portion of the optical fiber is fixed; and a second fixing member including a bendable middle bone (backbone), a grip portion for griping the first fixing member on one end side of the middle bone, and an optical fiber fixing portion for fixing the optical fiber to the middle bone on the other end side of the middle bone. 
     According to the above-described configuration, the middle bone of the second fixing member is bent, thereby making it possible to obtain the optical connecting component capable of bending and holding the optical fiber with any curvature without requiring a circuit board having a predetermined curved surface or a member having a curved hole. 
     (2) The mid bone may be bent, and the optical fiber may be bent along the middle bone. According to the above-described configuration, the first fixing member is mounted on the second fixing member in which the middle bone is bent to any curvature and shape in advance, and the optical fiber is fixed along the middle bone, thereby making it possible to obtain the optical connecting component that bends and holds the optical fiber. 
     (3) The first fixing member may include a hole through which the one end portion of the optical fiber penetrates, and (4) the first fixing member may include two plate-shaped members that sandwich the one end portion of the optical fiber. According to the above-described configuration, a plurality of configurations can be selected as the first fixing member. 
     (5) The optical fiber fixing portion may be a clamp member that is provided on the middle bone and clamps the optical fiber, and (6) the optical fiber fixing portion may be an adhesive that allows the optical fiber to adhere to the middle bone. According to the above-described configuration, various methods can be adopted as a method for fixing the optical fiber to the middle bone of the second fixing member. (7) The second fixing member may be made of plastically deformable steel material. According to the above-described configuration, the second fixing member can be easily manufactured by punching and bending. 
     Details of Embodiments of the Present Disclosure 
     Hereinafter, a desirable embodiment according to an optical connecting component of the present disclosure will be described with reference to the drawings. In the following description, since a configuration denoted by the same reference sign even in a different drawing is regarded as the same configuration, the description thereof may be omitted. The present invention is not limited to examples in these embodiments, and includes all the modifications within the scope of matters described in the scope of the claims and within the scope equivalent thereto. As long as a combination of a plurality of embodiments can be performed, the present invention includes a combination of any embodiments. 
     First Embodiment 
       FIGS. 1A and 1B  are a front view and a side view illustrating an example of an optical fiber used in a splicing component of the present disclosure, respectively.  FIGS. 2A and 2B  are a front view and a side view illustrating an example of a first fixing member provided in the optical connecting component of the present disclosure in a state where the optical fiber is fixed thereto, respectively. An optical fiber  10  includes: at least one core  11  made of quartz glass; a clad  12  that is provided around a periphery of the core  11  and has a refractive index lower than that of the core  11 ; and a resin coating layer  14  covering a periphery of the clad  12 . The glass core  11  and the clad  12  form a glass fiber  13 . 
     As illustrated in  FIGS. 2A and 2B , for example, one end portions of four optical fibers  10  are fixed to a first fixing member  20 . In the embodiment, as illustrated in  FIG. 1 , the coating layer  14  at one end portion of the optical fiber  10  is stripped, the clad  12  of the glass fiber  13  is exposed, and the exposed glass fiber  13  is fixed to the first fixing member  20 . The first fixing member  20  is a member for aligning the optical fibers  10 , and is an approximately rectangular parallelepiped glass capillary member including pores  21 . An inner diameter of the pore  21  is slightly larger than an outer diameter of the glass fiber  13 , and when the glass fiber  13  is inserted into the pore  21 , the glass fiber  13  is loosely fitted and positioned so as to be movable back and forth. The first fixing member  20  and the glass fiber  13  are fixed to each other by filling a gap between the pore  21  and the glass fiber  13  with an adhesive by using a capillary phenomenon. 
       FIGS. 2C and 2D  are a front view and a side view illustrating another example of the first fixing member provided in the optical connecting component of the present disclosure in a state where the optical fiber is fixed thereto, respectively. A first fixing member  30  is formed of a V-groove circuit board  31  made of glass and a flat circuit board  32  also made of glass. The V-groove circuit board  31  includes, for example, four V-grooves  33  arranged in parallel, and each V-groove  33  has a size in which the glass fiber  13  can be placed. The flat circuit board  32  has a size that covers the respective V-grooves  33  of the V-groove circuit board  31  and has a flat shape. The glass fiber  13  is placed on each V-groove  33  of the V-groove circuit board  31 , and is covered with the flat circuit board  32 . The flat circuit board  32  is fixed to the V-groove circuit board  31  together with the glass fiber  13  with an adhesive. The first fixing member  30  including the V-groove circuit board  31  and the flat circuit board  32  has an approximately rectangular parallelepiped shape which is similar to that of the first fixing member  20 . 
     The optical fiber  10  fixed to the first fixing members  20  and  30  may be one or a plurality of optical fibers other than four, and may be an optical fiber ribbon formed by taping a plurality of optical fibers  10  arranged in parallel with a common coating. The optical fiber  10  may include a single core or a plurality of cores. Tips of the first fixing members  20  and  30  to which the optical fiber  10  is fixed are polished together with the glass fiber  13 , and are fixed to a circuit board on which an optical element is mounted, which is not illustrated, by, for example, an adhesive. Materials of the first fixing members  20  and  30  are desirably glass from a viewpoint of matching a coefficient of thermal expansion with the glass fiber  13 , and may be resin. 
     When the optical fiber  10  is fixed to the first fixing members  20  and  30 , the glass fiber  13  is exposed and fixed to the first fixing members  20  and  30 , and may be fixed thereto in a state where the coating layer  14  is provided thereon. Therefore, in the present disclosure, the term “optical fiber” indicates an optical fiber in which the coating layer is provided on the glass fiber, and also includes an optical fiber in which the coating layer is partially stripped and the glass fiber is exposed. In the embodiment, the first fixing members  20  and  30  are provided on one end side of the optical fiber  10 , and the above-described first fixing members  20  and  30  may be also mounted on the other end side of the optical fiber  10  and a tip thereof may be polished. 
       FIG. 3A  is a perspective view illustrating an example  40  of the second fixing member of the optical connecting component of the present disclosure.  FIG. 3B  is a plan view of the second fixing member  40 , and  FIG. 3C  is a side view of the second fixing member  40 . The second fixing member  40  is a member for bending the optical fiber  10  to any curvature, the first fixing member  20  to which the optical fiber  10  is fixed (alternatively, the first fixing member  30  may be used. Hereinafter, the first fixing member  20  will be described as an example.) is mounted on one end side thereof, and the optical fiber  10  itself is fixed to the other end side thereof. 
     As illustrated in  FIG. 3A , the second fixing member  40  includes: a bendable middle bone (backbone)  41  extending in the X-axis direction; a grip portion  42  provided at one end of the middle bone  41 ; and an optical fiber clamp piece  43  serving as an optical fiber fixing portion provided on the other end side of the middle bone  41 . The second fixing member  40  is made of a plastically deformable steel material such as stainless steel, and, for example, is obtained by punching and bending one stainless steel plate. A thickness of the second fixing member  40  is desirably equal to or greater than 0.2 mm from a viewpoint of predetermined intensity and ease of processing. 
     The grip portion  42  includes: a bottom side portion  42 A connected from the middle bone  41  and parallel to the middle bone  41 ; two side wall portions  42 B extending vertically from the bottom side portion  42 A with a predetermined space therebetween; and two upper side portions  42 C that are respectively connected to the two side wall portions  42 B and opposite to the bottom side portion  42 A, and has an approximately square shape in a YZ cross section. When the rectangular parallelepiped first fixing member  20  is mounted on the grip portion  42 , the upper side portion  42 C is bent so as to act as a leaf spring so that the bottom side portion  42 A and the upper side portion  42 C elastically hold the first fixing member  20  from a Z-axis direction. When the first fixing member  20  is mounted thereon, heights of the middle bone  41  and the bottom side portion  42 A are adjusted so that the optical fiber  10  is located on the middle bone  41 . in the embodiment, when the rectangular parallelepiped first fixing member  20  is mounted on the grip portion  42 , the first fixing member  20  is configured to be elastically held from the Z-axis direction, and the first fixing member  20  may be configured to be elastically held from a Y-axis direction by deforming the two side wall portions  42 B. 
     The middle bone  41  allows the optical fiber  10  to be bent along the optical fiber  10  in a longitudinal direction (X-axis direction). The other end portion of the middle bone  41  on a side opposite to the grip portion  42  serves as an optical fiber fixing portion for fixing the optical fiber  10 . In the embodiment, in order to fix the optical fiber  10 , the optical fiber clamp piece  43  that is punched with the middle bone  41  in an integrated manner and bent in the Z-axis direction is provided at the other end portion of the middle bone  41 . The optical fiber  10  is fixed to the middle bone  41  at the optical fiber fixing portion so that the optical fiber  10  is bent along the middle bone  41  when the middle bone  41  is bent. In order to fix the optical fiber  10  at the optical fiber fixing portion on the other end side of the middle bone  41 , in addition to using the optical fiber clamp piece  43 , for example, a clip member configured separately from the middle bone  41  may be used, or an adhesive may be used. 
     Next, a method for manufacturing the optical connecting component by using the first fixing member  20  and the second fixing member  40  will be described.  FIG. 4A  is a cross-sectional view illustrating an example in which the first fixing member is mounted on the second fixing member in a state where the second fixing member is not bent, and  FIG. 4B  is a cross-sectional view illustrating an example in which the first fixing member is mounted on the second fixing member in a state where the second fixing member is bent.  FIGS. 4A and 4B  illustrate a cross section of the optical fiber  10  and the first fixing member  20  taken along the line  4 A- 4 A of  FIG. 2D . The first fixing member  20  to which the optical fiber  10  is fixed is inserted into the second fixing member  40  from a minus side in the X-axis direction, the first fixing member  20  is fixed by the grip portion  42  of the second fixing member  40 , and the optical fiber  10  is placed along the middle bone  41 . Next, the optical fiber clamp piece  43  provided at the other end portion of the middle bone  41  is bent toward the middle bone  41 , and the optical fiber  10  is fixed at the other end side of the middle bone  41 . As described above, as a method for fixing the optical fiber  10  to the other end side of the middle bone  41 , a separate clip member and an adhesive may be used. 
     Next, as illustrated in  FIG. 4B , an optical connecting component  1  is obtained by applying an external force in a normal direction of the middle bone  41  and deforming the middle bone  41  into a desired circular arc shape to form a bent portion  44  in the middle bone  41 , At that time, for example, it is desirable to use a rod-shaped jig  50  including a circular arc portion of a predetermined curvature, to allow the middle bone  41  to be placed along the circular arc portion of the rod-shaped jig  50 , and to bend the middle bone  41  while pressing the rod-shaped jig  50 . Since the optical fiber  10  is fixed to the middle bone  41  by the first fixing member  20  and the optical fiber fixing portion, as a result, it is possible to manufacture the optical connecting component in which a part of the optical fiber  10  having a desired circular arc shape is bent. The middle bone  41  may be formed in an S shape by applying an external force a plurality of times within a length range of the middle bone  41  in the longitudinal direction and providing the bent portions at a plurality of locations. As described above, in the embodiment, since the middle bone  41  can be bent into a desired shape, a circuit board having a predetermined curved surface or a member having a curved hole is not required. 
     Second Embodiment 
       FIG. 5  is a perspective view illustrating another example of the second fixing member of the optical connecting component of the present disclosure. In the first embodiment, the middle bone  41  of the second fixing member  40  is linearly formed, and the bent portion is formed after fixing the optical fiber  10 , and in the embodiment, the second fixing member  40  including the bent portion  44  formed in the middle bone  41  with a predetermined curvature is used. In the embodiment, first, the first fixing member  20  on which the optical fiber  10  is mounted is mounted on the grip portion  42  provided at one end portion of the second fixing member  40 , Next, the optical fiber  10  is bent along the bent portion  44  of the middle bone  41 , and the optical fiber  10  is fixed to the middle bone  41  by the optical fiber clamp piece  43  at the other end portion of the middle bone  41 . In order to fix the optical fiber  10  to the middle bone  41 , a separate clip member and an adhesive may be used instead of the optical fiber clamp piece  43 . In the embodiment, since the middle bone  41  of the second fixing member  40  can be bent into a desired shape, it is possible to easily obtain the optical connecting component including the middle bone  41  bent into a desired shape without requiring a circuit board having a predetermined curved surface or a member having a curved hole. 
     REFERENCE SIGNS LIST 
       1 : optical connecting component 
       10 : optical fiber 
       11 : core 
       12 : clad 
       13 : glass fiber 
       14 : coating layer 
       20 ,  30 : first fixing member 
       21 : pore 
       31 : V-groove circuit board 
       32 : flat circuit board 
       33 : V-groove 
       40 : second fixing member 
       41 : middle bone (backbone) 
       42 : grip portion 
       42 A: bottom side portion 
       42 B: side wall portion 
       42 C: upper side portion 
       43 : optical fiber damp piece 
       44 : bent portion 
       50 : rod-shaped jig