JP2014095861A - Optical connector and optical component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical connector having small splice loss and high reliability, and an optical component.SOLUTION: An optical fiber 3 is arranged such that the tip part thereof projects from a V-shaped groove 14 over an adhesive-filled groove 33, and the tip part and a ferrule wall 31 are separated from each other. The adhesive filling the periphery of the optical fiber 3 including the gap between the tip part and the ferrule wall 31, and the adhesive-filled groove 33 is cured to fix the optical fiber 3 to a ferrule 2 with a lens.

Description

  The present invention relates to a collimated optical connector and an optical component.

  2. Description of the Related Art Conventionally, there has been known a collimator type optical connector in which an optical fiber having a lens-attached ferrule attached to the tip is disposed oppositely and optical fibers are optically connected to each other through a lens (collimator lens) of the lens-equipped ferrule.

  In this collimated optical connector, in one connector part, the light emitted from one optical fiber and spread is converted into parallel light by a lens and emitted, and in the other connector part, the incident parallel light is converted into a lens. And is incident on the other optical fiber.

  In collimated optical connectors, the beam diameter is large between the lenses, so that the optical loss due to the relative displacement between the connector portions (relative displacement between the opposing ferrules with lens) is relatively small. It is possible.

  In such an optical connector, a ferrule with a lens provided with a fiber fixing portion formed integrally with a lens and having a V-groove for placing an optical fiber is used, and the optical fiber is placed in the V-groove by placing the optical fiber in the V-groove. Passive mounting that performs alignment with the lens is widely used.

  More specifically, in an optical connector that performs passive mounting, an optical fiber is placed in the V groove of the fiber fixing portion, an adhesive is filled around the optical fiber, and the optical fiber is moved to the V groove side by a pressing plate. The optical fiber is fixed to the ferrule with a lens by curing the pressing adhesive.

  In addition, there exists patent documents 1-3 as prior art document information relevant to invention of this application.

JP 2008-151843 A JP 2009-145427 A JP 2003-43313 A

  However, when performing passive mounting as described above, there is a problem that stress concentration is likely to occur at the tip of the optical fiber, and bubbles and peeling of the adhesive are likely to occur at the tip of the optical fiber. When bubbles or peeling occurs in the adhesive, connection loss increases or reliability deteriorates.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical connector and an optical component with low connection loss and high reliability.

  The present invention was devised to achieve the above-mentioned object, and an optical fiber having a lens-attached ferrule attached to the tip is arranged oppositely, and the optical fibers are optically connected via the lens of the lens-equipped ferrule. In the optical connector, the ferrule with a lens includes a fiber fixing portion in which a V groove for mounting the optical fiber is formed and is formed integrally with the lens, and the optical fiber is mounted in the V groove of the fiber fixing portion. And the optical fiber is fixed to the ferrule with a lens by filling the periphery of the optical fiber with an adhesive, pressing the optical fiber against the V-groove side with a pressing plate, and curing the adhesive. The fiber fixing portion is formed integrally with a ferrule wall to which the lens is fixed, and on the opposite side of the ferrule wall from the lens. In addition, a pedestal portion on which the V-groove is formed and the optical fiber is placed on the surface thereof, and the ferrule wall side end of the surface of the pedestal portion are formed so as to communicate with the V-groove, An adhesive filling groove filled with the adhesive, and the optical fiber protrudes from the V groove onto the adhesive filling groove, and the tip and the ferrule wall Is fixed to the ferrule with lens by curing the adhesive filled around the optical fiber including the gap between the ferrule wall and the adhesive filling groove. It is an optical connector.

  The adhesive filling groove may be formed with a tip position determining projection that contacts the cladding of the tip surface of the optical fiber and determines the tip position of the optical fiber.

  The two lens-equipped ferrules arranged to face each other may be arranged to be rotated by 180 degrees relative to the circumferential direction of the optical fiber.

  The ferrule with a lens is formed by injection molding, and as the ferrule with a lens attached to the ends of the two optical fibers, an injection mold using the same mold may be used.

  Further, the present invention is an optical component in which a ferrule with a lens is attached to the tip of an optical fiber, and the ferrule with a lens is a fiber in which a V-groove for placing the optical fiber is formed and formed integrally with the lens The optical fiber is placed in the V-groove of the fiber fixing portion, and an adhesive is filled around the optical fiber, and the optical fiber is pressed against the V-groove side by a pressing plate, and the bonding is performed. By curing the agent, the optical fiber is configured to be fixed to the ferrule with a lens, and the fiber fixing portion is integrated with a ferrule wall on which the lens is fixed and an opposite side of the ferrule wall to the lens. A pedestal part on which the V-groove is formed and the optical fiber is placed; and an end of the surface of the pedestal part on the ferrule wall side An adhesive-filled groove formed to communicate with the V-groove and filled with the adhesive, and the optical fiber has a tip protruding from the V-groove onto the adhesive-filled groove. In addition, the adhesive filled in the periphery of the optical fiber including the gap between the ferrule wall and the adhesive filling groove is hardened. Thus, the optical component is fixed to the ferrule with a lens.

  According to the present invention, it is possible to provide an optical connector and an optical component with low connection loss and high reliability.

It is a figure which shows the optical connector which concerns on one embodiment of this invention, (a) is a perspective view, (b) is sectional drawing and the principal part enlarged view. It is a figure explaining the connection state of the optical connector of FIG. It is a figure which shows the ferrule with a lens in the optical connector of FIG. 1, (a) is a perspective view, (b) is a perspective view which abbreviate | omitted the glass plate, (c) is 3C-3C sectional view taken on the line of (a). . It is sectional drawing which shows the modification of the ferrule with a lens used for the optical connector of FIG. (A) is a perspective view of the housing in the optical connector of FIG. 1, (b) is a sectional view when a ferrule with a lens is inserted into the housing. It is a perspective view of the housing in the optical connector of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1A and 1B are diagrams showing an optical connector according to the present embodiment, in which FIG. 1A is a perspective view, and FIG. 1B is a cross-sectional view and an enlarged view of a main part thereof.

  As shown in FIGS. 1 (a) and 1 (b), the optical connector 1 has an optical fiber 3 with a lens-attached ferrule 2 attached at the tip thereof, and the optical fibers 3 are connected to each other via the lens 4 of the lens-equipped ferrule 2. Are optically connected.

  The optical connector 1 is configured to optically connect the optical fibers 3 by fitting the connector portions 5 provided at the distal ends of the two optical fibers 3 to each other. In the present embodiment, since the same connector is used as both the connector parts 5, the two connector parts 5 are not particularly distinguished from each other, but it is naturally possible to use different connector parts 5 having different shapes. .

  The connector unit 5 includes a lens-equipped ferrule 2 attached to the tip of the optical fiber 3 and a cylindrical housing 6 attached to the tip of the lens-equipped ferrule 2. An optical component 100 according to the present embodiment is obtained by attaching the ferrule 2 with a lens to the tip of the optical fiber 3.

  The ferrule 2 with a lens is made of resin and is formed by injection molding. The lens 4 is a collimating lens and is integrated with the resin portion by being inserted at the time of injection molding. The detailed shape of the ferrule 2 with a lens will be described later.

  The tip of the ferrule 2 with a lens is inserted and fixed in the hollow portion 7 of the housing 6. The housing 6 includes a flange portion 8 having a substantially rectangular shape (rectangular shape with rounded corners) fixed to a device or the like, and a cylindrical ferrule holding portion 9 integrally formed behind the flange portion 8. , Is composed of. The flange portion 8 is formed with a screw hole 8a through which a fixing screw is passed when the flange portion 8 is fixed to a device or the like. The housing 6 is made of, for example, metal. On the side opposite to the insertion side of the lens-equipped ferrule 2 in the hollow portion 7, a glass plate 21 is fixed with an adhesive or the like so as to close the opening of the hollow portion 7. The glass plate 21 can be omitted.

  The optical connector 1 is configured such that both optical fibers 3 are fixed in a face-to-face arrangement by abutting and fixing the front end surfaces of both housings 6 (the front end surfaces of the flange portion 8). In the present embodiment, the two housings 6 are fixed by a fixing member (not shown). However, a mechanism for fixing the two housings 6 may be provided on the housing 6 itself.

  In the optical connector 1 according to the present embodiment, the ferrules 2 with both lenses are arranged to rotate 180 degrees relative to the circumferential direction of the optical fiber 3. That is, the optical connector 1 is configured such that when the two connector portions 5 are fixed, the opposing ferrules 2 with both lenses are turned upside down and face each other.

  As described above, in the ferrule 2 with a lens molded by injection molding, the focal position of the lens 4 and the mounting position of the optical fiber 3 (that is, the center position of the lens 4 and the center of the optical fiber 3 are determined depending on the manufacturing tolerance of the mold. A slight tolerance occurs in the position).

  In the present embodiment, as shown in FIG. 2, the ferrule 2 with both lenses is disposed by being rotated by 180 degrees relative to the circumferential direction of the optical fiber 3. The direction of displacement of the center position of the optical fiber 3 with respect to the position is the opposite direction (the center position of both optical fibers 3 is point-symmetric with respect to the center position of the lens 4). As a result, even if the center positions of the lens 4 and the optical fiber 3 are deviated, the deviation is optically canceled. Therefore, if the center positions of the opposing lenses 4 are accurately aligned, Optical connection loss can be minimized. 2 shows the positional relationship between the lens 4, the optical fiber 3, and the V-groove 14 when viewed from the front end side of the housing 6.

  Here, specific shapes of the ferrule 2 with a lens and the housing 6 will be described in detail. First, the ferrule 2 with a lens will be described.

  As shown in FIGS. 1 and 3, the ferrule 2 with a lens includes a fiber fixing portion 10 in which a V-groove 14 for placing the optical fiber 3 is formed and formed integrally with the lens 4, and a rear portion of the fiber fixing portion 10. And a cylindrical portion 11 formed integrally with an insertion hole 12 through which the optical fiber 3 passes.

  The fiber fixing portion 10 is formed integrally with a ferrule wall 31 to which the lens 4 is fixed (formed integrally with the lens 4) and the ferrule wall 31 on the opposite side to the lens 4, and a V-groove 14 is formed on the surface thereof. And a pedestal portion 32 on which the optical fiber 3 is placed. The pedestal portion 32 has a shape in which a concave section (notch) 13 having a rectangular cross section is formed on the side surface of a cylindrical body (solid cylindrical body) having substantially the same diameter as the lens 4.

  The optical fiber 3 is placed in the V-groove 14 of the fiber fixing portion 10, and an adhesive (not shown) is filled around the optical fiber 3, and the optical fiber 3 is inserted into the V-groove 14 by a pressing plate 15 such as a glass plate. The optical fiber 3 is fixed to the ferrule 2 with a lens by curing the adhesive while pressed to the side. Also, the insertion hole 12 of the cylindrical portion 11 is filled with an adhesive and cured. For example, an ultraviolet curable resin can be used as the adhesive.

  In the optical connector 1, the manufacturing tolerance of the mold described above is a relative positional shift between the lens 4 and the V groove 14. If the relative positions of the lens 4 and the V-groove 14 are shifted, the center positions of the lens 4 and the optical fiber 3 are shifted.

  Now, in the optical connector 1 according to the present embodiment, as shown in FIGS. 1B and 3B, the end of the surface of the pedestal portion 32 on the ferrule wall 31 side communicates with the V groove 14. As described above, the adhesive filling groove 33 filled with the adhesive is formed. The adhesive filling groove 33 is a groove formed in a concave shape on the surface of the pedestal portion 32, and is formed so as to extend on both sides around the V groove 14 in a top view.

  The optical fiber 3 is disposed so that the tip end portion protrudes from the V groove 14 onto the adhesive filling groove 33 and the tip end portion and the ferrule wall 31 are separated from each other. The optical fiber 3 is fixed to the ferrule 2 with a lens by curing the adhesive filled around the optical fiber 3 including the gap between the tip portion and the ferrule wall 31 and the adhesive filling groove 33. The

  When the optical fiber 3 is mounted, bubbles are likely to be generated particularly at the corner between the ferrule wall 31 and the pedestal 32 (the lower right corner in the enlarged view of FIG. 1B). In the present embodiment, since the adhesive filling groove 33 is formed, the flow when filling the adhesive is improved, and the generation of bubbles can be reduced. Further, by forming the adhesive filling groove 33, it is possible to separate the corner portion where bubbles are likely to be generated from the optical fiber 3, and even if bubbles are generated at the corner portions, connection loss due to the bubbles is reduced. The increase can be suppressed. Furthermore, the adhesive filled in the adhesive filling groove 33 can relieve stress concentration between the optical fiber 3 and the lens-equipped ferrule 2 (fiber fixing portion 10), and the adhesive peels off due to the stress concentration. Can be suppressed.

  In the present embodiment, since the tip of the optical fiber 3 and the ferrule wall 31 are separated from each other and the gap between them is filled with the adhesive, the flow of the adhesive at the time of filling the adhesive is improved, and The tip of the optical fiber 3 is firmly fixed by the adhesive filled in the gap, and the peeling of the adhesive due to stress concentration can be suppressed. In this embodiment, since the tip of the optical fiber 3 and the ferrule wall 31 are separated from each other, the lens 4 is designed so that its focal point is behind the ferrule wall 31. There is a need.

  The optical fiber 3 needs to be accurately positioned so that the tip position thereof coincides with the focal position of the lens 4. Therefore, as shown in FIG. 4, the adhesive filling groove 33 is brought into contact with the cladding 3b (position away from the core 3a) of the distal end surface of the optical fiber 3 to determine the distal end position of the optical fiber 3. By forming the projections 34, the positioning of the tip position of the optical fiber 3 can be facilitated, and the productivity can be improved.

  Returning to FIGS. 1 and 3, the cylindrical portion 11 is formed in a shape in which both sides of a cylindrical body (hollow cylindrical body) are cut out in parallel (parallel to the surface of the base portion 32 of the fiber fixing portion 10). Of the two opposing parallel portions 16 formed by the notches, the locking claw 18 of the lock mechanism 17 to be described later is provided on the parallel portion 16 on the recess 13 side (the side where the pressing plate 15 is provided, the upper side in FIG. 1). A locking projection 19 for locking is formed. Further, an over-insertion preventing protrusion 20 that interferes with the engaging claw 18 and prevents the lens ferrule 2 from being excessively inserted into the housing 6 is formed on the parallel portion 16 behind the engaging protrusion 19.

  As the ferrule 2 with both lenses, it is necessary to use a lens in which the center position of the lens 4 and the optical fiber 3 are equal. Therefore, as the ferrule 2 with both lenses, one that is injection-molded using the same mold is used.

  Next, the housing 6 will be described.

  As shown in FIG. 2, an alignment projection 22 and a groove 23 for accommodating the projection 22 are formed on the distal end surfaces of both housings 6 (the distal end surface of the flange portion 8). In the present embodiment, the protrusion 22 and the groove 23 are provided only when the ferrule 2 with both lenses is rotated by 180 degrees relative to the circumferential direction of the optical fiber 3 (with the ferrule 2 with both lenses turned upside down, left and right). Only) formed to fit.

  Specifically, in the present embodiment, as the housing 6, one or more (two in this case) protrusions 22 are formed on one side of the front end surface (one side in the vertical direction in FIG. 2), and the other side ( In FIG. 2, one or more (here, two) grooves 23 corresponding to the protrusions 22 are formed on the other side in the vertical direction, and a straight line connecting the protrusions 22 and the grooves 23 when the front end surface is viewed from the front. What was comprised so that it might become a rectangular shape was used. With this configuration, both housings 6 having the same shape are used, but both housings 6 are not fixed in the wrong direction, and the number of parts can be reduced.

  Note that the structure that allows the two ferrules with a lens 2 to be fitted only when the ferrule 2 with a lens is rotated by 180 degrees relative to the circumferential direction of the optical fiber 3 is not limited to this. The shape may be an asymmetrical shape instead of a circular shape, and the two housings 6 do not have the same shape, but the protrusions 22 and the grooves 23 can be formed asymmetrically. In addition to the protrusions 22 and the grooves 23, it is of course possible to separately provide a mechanism for regulating the orientation when the housings 6 are fitted.

  As shown in FIGS. 5 and 6, the inner wall of the housing 6 (the inner wall of the flange portion 8) projects into the hollow portion 7 and sandwiches the distal end portion of the ferrule 2 with a lens for positioning in the circumferential direction. A protrusion 24 is formed. By forming the tip positioning protrusion 24, the tip of the ferrule 2 with a lens is not rattled, and the lens 4 can be accurately positioned.

  In the present embodiment, three tip positioning protrusions 24 are formed at equal intervals along the circumferential direction of the hollow portion 7, but the number of tip positioning protrusions 24 is not limited to this. However, in order to improve the positioning accuracy of the lens 4, it is desirable to form three or more tip positioning protrusions 24.

  The tip positioning protrusions 24 are desirably formed in a horizontally long shape so that the protruding length gradually increases toward the tip side. This is because the lens-equipped ferrule 2 can be easily inserted and the lens 4 can be accurately positioned by firmly holding the tip of the lens-equipped ferrule 2. The same effect can be obtained by forming the fiber fixing portion 10 of the ferrule 2 with a lens so that the diameter gradually increases toward the proximal end without changing the protruding length of the protrusion 24 for positioning the distal end. Is possible.

  As shown in FIGS. 1, 5, and 6, the housing 6 has a locking mechanism having a locking claw 18 that locks the ferrule 2 with a lens to the housing 6 by locking with a locking projection 19 formed on the ferrule 2 with a lens. 17. A through hole 18 a is formed in the locking claw 18, and a rotation shaft (not shown) is provided so as to penetrate the through hole 18 a and the through hole 9 a formed in the ferrule holding part 9. A locking claw 18 is provided so as to be rotatable around an axis.

  The locking claw 18 is biased by a spring 25 and is configured to press the ferrule 2 with lens (tubular portion 11) inserted into the hollow portion 7 by the spring force of the spring 25. Further, a stopper 26 for locking the locking claw 18 is provided so that the locking claw 18 is not unintentionally released. The lock mechanism 17 is provided only on one side of the housing 6, and the orientation of the lens ferrule 2 can be distinguished by the presence or absence of the lock mechanism 17.

  By the way, even if the tip of the ferrule 2 with a lens is fixed by the tip positioning protrusion 24, if the rear of the lens ferrule 2 is pressed by the locking claw 18 and the lens ferrule 2 is tilted, the optical axis is shifted. This increases the optical connection loss. Therefore, in the present embodiment, an inclination suppressing protrusion 27 is formed on the inner wall of the housing 6 at a position facing the locking claw 18 to suppress the inclination of the ferrule 2 with a lens against the pressing by the locking claw 18. ing.

  In the present embodiment, one inclination suppressing protrusion 27 is formed at a position facing the locking claw 18, but the inclination suppressing protrusion 27 can be divided into a plurality along the circumferential direction of the hollow portion 7. is there. In this case, the inclination of the ferrule 2 with a lens can be suppressed by forming the inclination suppression protrusions 27 on both sides without forming the inclination suppression protrusions 27 directly below the locking claws 18.

  As described above, in the optical connector 1 and the optical component 100 according to the present embodiment, the fiber fixing portion 10 is formed so as to communicate with the V groove 14 at the end of the surface of the pedestal portion 32 on the ferrule wall 31 side. The optical fiber 3 is provided with an adhesive filling groove 33 filled with an adhesive, and the optical fiber 3 protrudes from the V groove 14 onto the adhesive filling groove 33, and the tip part and the ferrule wall 31 are provided. Are fixed to the ferrule 2 with a lens by curing the adhesive filled around the optical fiber 3 including the gap between the ferrule wall 31 and the adhesive filling groove 33. ing.

  With this configuration, the flow of the adhesive when filling the adhesive can be improved to suppress the generation of bubbles, and the optical fiber 3 can be formed with the adhesive filled in the adhesive filling groove 33. It is possible to relieve stress concentration between the optical fiber 3 and the lens-equipped ferrule 2 and to firmly fix the optical fiber 3 by filling an adhesive between the optical fiber 3 and the ferrule wall 31. It is possible to suppress peeling of the adhesive due to concentration.

  Therefore, according to the present invention, it is possible to realize the optical connector 1 and the optical component 100 with low connection loss and high reliability, in which bubbles and peeling of the adhesive are suppressed.

  In addition, by forming a tip position determining projection 34 for determining the tip position of the optical fiber 3 in contact with the clad 3 b of the tip surface of the optical fiber 3 in the adhesive filling groove 33, the tip position of the optical fiber 3 is determined. Positioning can be facilitated and productivity can be improved.

  Further, in the optical connector 1 according to the present embodiment, the ferrule 2 with both lenses is disposed by being rotated by 180 degrees relative to the circumferential direction of the optical fiber 3.

  As a result, the center position of both optical fibers 3 after mounting becomes a point-symmetrical position with respect to the center position of the lens 4, and the center positions of the lens 4 and the optical fiber 3 are shifted due to the manufacturing tolerance of the mold. Even in such a case, since the optical shift is canceled, if the center positions of the opposing lenses 4 are accurately aligned, it is possible to minimize the light connection loss. That is, according to the optical connector 1, it is possible to suppress the connection loss of light due to the tolerance between the focal position of the lens 4 and the mounting position (V groove 14) of the optical fiber 3.

  The present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Optical connector 2 Ferrule with lens 3 Optical fiber 4 Lens 5 Connector part 6 Housing 10 Fiber fixing part 14 V groove 15 Holding plate 31 Ferrule wall 32 Base part 33 Adhesive filling groove 100 Optical component

Claims (5)

In an optical connector in which an optical fiber having a lens-attached ferrule attached to the tip is disposed oppositely and optical fibers are optically connected to each other via the lens of the lens-equipped ferrule,
The ferrule with a lens includes a fiber fixing portion formed integrally with the lens and having a V-groove for mounting the optical fiber, and the optical fiber is mounted in the V-groove of the fiber fixing portion, An adhesive is filled around the optical fiber, the optical fiber is pressed against the V-groove side by a pressing plate, and the adhesive is cured to fix the optical fiber to the ferrule with a lens,
The fiber fixing part is formed integrally with a ferrule wall to which the lens is fixed, and on the opposite side of the ferrule wall from the lens, and the V-groove is formed on the surface thereof, and the optical fiber is placed thereon. A pedestal, and an adhesive-filled groove that is formed to communicate with the V-groove at the end of the surface of the pedestal on the ferrule wall side, and is filled with the adhesive;
The optical fiber is disposed such that a tip portion thereof protrudes from the V-groove onto the adhesive filling groove, and the tip portion and the ferrule wall are separated from each other, and a gap between the ferrule wall is provided. The optical connector is fixed to the ferrule with a lens by curing an adhesive filled around the optical fiber including the adhesive filling groove. The optical connector according to claim 1, wherein the adhesive filling groove is formed with a tip position determination protrusion that contacts the clad of the tip surface of the optical fiber and determines the tip position of the optical fiber. The optical connector according to claim 1, wherein the ferrules with both lenses disposed opposite to each other are disposed by being rotated 180 degrees relative to a circumferential direction of the optical fiber. The ferrule with a lens is formed by injection molding,
The optical connector according to claim 3, wherein the ferrule with a lens attached to the tips of both optical fibers is an injection-molded one using the same mold. An optical component having a lens-equipped ferrule attached to the tip of an optical fiber,
The ferrule with a lens includes a fiber fixing portion formed integrally with the lens and having a V-groove for mounting the optical fiber, and the optical fiber is mounted in the V-groove of the fiber fixing portion, An adhesive is filled around the optical fiber, the optical fiber is pressed against the V-groove side by a pressing plate, and the adhesive is cured to fix the optical fiber to the ferrule with a lens,
The fiber fixing part is formed integrally with a ferrule wall to which the lens is fixed, and on the opposite side of the ferrule wall from the lens, and the V-groove is formed on the surface thereof, and the optical fiber is placed thereon. A pedestal, and an adhesive-filled groove that is formed to communicate with the V-groove at the end of the surface of the pedestal on the ferrule wall side, and is filled with the adhesive;
The optical fiber is disposed such that a tip portion thereof protrudes from the V-groove onto the adhesive filling groove, and the tip portion and the ferrule wall are separated from each other, and a gap between the ferrule wall is provided. The optical component is fixed to the ferrule with a lens by curing an adhesive filled around the optical fiber including the adhesive filling groove.