Optical connector and method for manufacturing optical connector

Abstract

[Problem] To provide an optical connector in which, by molding protruding parts and recessed parts integrally with the optical connector instead of guide pins, the number of components is reduced, a fitting error caused when each guide pin is inserted into a guide pin hole is suppressed or prevented, accurate alignment between the optical connector and ends of optical fibers becomes possible, and thus an optical connection loss in each optical fiber can be suppressed, and a method for manufacturing the optical connector. [Solution] This optical connector is manufactured by integrally providing insertion holes that make it possible to arrange optical fibers in a single row and integrally providing a plurality of protruding parts (2a, 2b) and recessed parts (3a, 3b) coaxially on each end surface. Moreover, by providing a convex step part (6a) on one end surface and a concave step part (6b) on the other end surface (back surface side), positioning by fitting engagement between the convex step part (6a) and the concave step part (6b) is used in addition to positioning by the convex parts (2a, 2b) and the concave parts (3a, 3b), thereby further improving positioning accuracy.

Description

Optical Connector and Method for Manufacturing Optical Connector

[0001] The present invention relates to an optical connector and a method for manufacturing an optical connector.

[0002] Optical connectors are used for optical connection between optical fibers. An example of such an optical connector is the optical connector disclosed in Patent Document 1 (referred to as a ferrule for an optical connector in Patent Document 1). Patent Document 1 describes a ferrule for an optical connector for positioning and holding an optical fiber ribbon consisting of a plurality of coated optical fibers with their coatings removed.

[0003] The ferrule for an optical connector in Patent Document 1 has a housing portion, and a plurality of long-groove-shaped optical fiber insertion holes for inserting, positioning and holding a plurality of optical fibers are formed on the connection end face of the housing portion. The plurality of optical fiber insertion holes are arranged and formed in a matrix at mutual intervals on the connection end face along a first direction and a second direction orthogonal to the first direction.

[0004] Furthermore, in the ferrule for an optical connector of Patent Document 1, two guide pin holes are formed in the housing portion, and guide pins are inserted into the respective guide pin holes for alignment of the ferrule for an optical connector.

[0005] Japanese Patent No. 5203001

[0006] However, in an optical connector using guide pins, a fitting error occurs when inserting the guide pins into the guide pin holes, and the fitting error causes positional displacement of the optical connector, which may also cause displacement in the alignment of the end portions of the optical fibers. When positional displacement occurs at the end portions of the optical fibers, there is a risk that connection loss occurs in the optical connection between the optical fibers. In addition, since it is necessary to prepare guide pins, the number of components increases, which makes the assembly work complicated.

[0007] The present invention has been made in view of the above problems, and aims to provide an optical connector and a method for manufacturing an optical connector that reduces the number of parts by integrally molding protrusions and recesses to the optical connector instead of guide pins, suppresses or prevents fitting errors that occurred when inserting guide pins into guide pin holes, enables accurate alignment between the optical connector and the end of the optical fiber, and suppresses optical connection loss in each optical fiber.

[0008] The aforementioned problems are solved by the present invention as described below. Specifically, the optical connector of the present invention is characterized by having an insertion hole that allows optical fibers to be arranged in a single row, and having a plurality of protrusions and recesses integrally molded on each end face on the same axis. Furthermore, in a preferred embodiment of the optical connector of the present invention, it is preferable that a convex step is integrally molded on the end face where the insertion hole is provided, and a concave step is integrally molded on the end face opposite to the end face, and that the convex step and the concave step are able to fit together.

[0009] Furthermore, the manufacturing method of the optical connector of the present invention is characterized by providing an insertion hole that allows optical fibers to be arranged in a single row by integral molding, and by providing a plurality of protrusions and recesses on each end face coaxially by integral molding.

[0010] According to the optical connector or method for manufacturing an optical connector of the present invention, since protrusions and recesses are integrally molded into the optical connector instead of guide pins, fitting errors that occurred when inserting guide pins into guide pin holes are suppressed or prevented. Therefore, accurate alignment between the optical connector and the end of the optical fiber becomes possible, and optical connection loss in each optical fiber can be suppressed. In addition, since there is no need to use guide pins, the number of parts is reduced.

[0011] This is a perspective view showing the appearance of an optical connector according to an embodiment of the present invention. This is a plan view of the optical connector of Figure 1. This is a front view of the optical connector of Figure 1. This is a rear view of the optical connector of Figure 1. This is a front view showing the optical fiber arranged in the insertion hole of the optical connector of Figure 1. This is an enlarged view of elliptical portion A in Figure 5. This is an enlarged view of circular portion B in Figure 6. This is an explanatory diagram showing a state in which multiple optical connectors according to an embodiment of the present invention are connected. This is an explanatory diagram showing examples of changes in the formation state of the convex and concave portions. This is an explanatory diagram showing examples of changes in the shape of the convex portion. This is an explanatory diagram showing examples of changes in the shape of the optical fiber insertion hole. As an example of changes, this is an explanatory diagram showing the shape of one insertion hole into which 16 optical fibers can be inserted. This is an explanatory diagram showing examples of changes in the formation state of the optical fiber insertion hole. As an example of changes, this is a perspective view showing the appearance of an optical connector in which convex and concave portions are provided on both end faces having optical fiber insertion holes. This is a plan view of the optical connector of Figure 14.

[0012] The first feature of the optical connector according to this embodiment is that it is an optical connector that has insertion holes for arranging optical fibers in a single row, and multiple protrusions and recesses are integrally molded on each end face on the coaxial surface.

[0013] A second feature of this embodiment is that it is a method for manufacturing an optical connector that provides an insertion hole for arranging optical fibers in a single row through integral molding, and also provides multiple protrusions and recesses on each end face coaxially through integral molding.

[0014] A third feature of this embodiment is that it is a method for manufacturing optical connectors in which the integral molding is done by injection molding.

[0015] With these configurations or methods, protrusions and recesses are integrally molded into the optical connector instead of guide pins, thus suppressing or preventing fitting errors that occurred when inserting guide pins into guide pin holes. Therefore, accurate alignment between the optical connector and the end of the optical fiber becomes possible, and optical connection loss in each optical fiber 5 can be suppressed. In addition, since there is no need to use guide pins, the number of parts is reduced.

[0016] Furthermore, since both the convex and concave portions are integrally molded into the optical connector, both the end face of the optical connector with the convex portion and the end face of the optical connector with the concave portion serve as connection surfaces. By fitting the convex portion into the concave portion between multiple optical connectors, it becomes possible to optically connect multiple optical connectors simultaneously.

[0017] A fourth feature of this embodiment is that the optical connector has a cylindrical protrusion, a circular retaining hole in the recess, and a chamfered end on the protrusion.

[0018] A fifth feature of this embodiment is that it is a method for manufacturing an optical connector in which the convex portion is integrally molded into a cylindrical shape, the concave portion is integrally molded into a circular stopper hole shape, and the end of the convex portion is chamfered integrally.

[0019] These configurations or methods prevent chipping and cracking during the insertion or removal of the protrusions and recesses of the optical connector. Furthermore, the insertion and removal processes of the protrusions and recesses become easier. Additionally, cracking and chipping of the protrusions and recesses during the integral molding process are prevented, further simplifying the integral molding process.

[0020] Another sixth feature of this embodiment is that the optical connector is made of zirconia.

[0021] Another feature of this embodiment is that it is a method for manufacturing an optical connector in which zirconia is used as the material for forming the optical connector.

[0022] These configurations or methods make it possible to suppress the occurrence of chipping in integrally molded products.

[0023] An eighth feature of this embodiment is that it is an optical connector in which multiple insertion holes are provided, each insertion hole is capable of arranging multiple optical fibers in a line, each insertion hole is formed by a plane and multiple V-grooves, one optical fiber is inserted into each V-groove and the optical fiber is supported at three points, and the central axes of each core of the optical fibers are arranged in a line.

[0024] Furthermore, the ninth feature of this embodiment is a method for manufacturing an optical connector in which multiple insertion holes are provided, each insertion hole is capable of arranging multiple optical fibers in a line, the shape of each insertion hole is formed with a plane and multiple V-grooves, and one optical fiber is inserted into each V-groove to support the optical fibers at three points, and the central axes of each core of the optical fibers are arranged in a line.

[0025] These configurations or methods facilitate the positional management of each optical fiber end. Furthermore, by supporting the optical fiber at three points, each optical fiber can be securely held, enabling high-precision linear arrangement of optical fibers while maintaining an extremely small pitch interval.

[0026] Another feature of this embodiment is that the optical connector is such that the optical fibers are arranged with a gap of 0.001 mm or more and 0.124 mm or less between each fiber.

[0027] Another feature of this embodiment is that it is a method for manufacturing an optical connector in which optical fibers are arranged with a gap of 0.001 mm or more and 0.124 mm or less between each fiber.

[0028] With these configurations or methods, by arranging the optical fibers with a gap of 0.001 mm to 0.124 mm between each fiber, it becomes possible to achieve a highly accurate single-row arrangement of optical fibers even when the gap is narrowed to a numerical range of 0.001 mm to 0.124 mm.

[0029] Another feature of this embodiment is that the optical connector has four to sixteen optical fibers arranged in each insertion hole.

[0030] Another feature of this embodiment is that it is a method for manufacturing an optical connector in which the number of optical fibers arranged in each insertion hole is between 4 and 16.

[0031] These configurations or methods make it possible to set the maximum number of optical fibers within a range where deformation of the insertion hole can be suppressed or prevented. Therefore, bulging of the insertion hole shape and bending of the central part of the insertion hole can also be suppressed or prevented.

[0032] Furthermore, the fourteenth feature of this embodiment is that a convex step portion is integrally molded on the end face on which the insertion hole is provided, and a concave step portion is integrally molded on the end face opposite to the end face, the convex step portion and the concave step portion are interlocked, the height t3 of the convex step portion and the height t4 of the concave step portion satisfy the relationship t3 = t4, and the relationship t1 ≤ t3 is satisfied between the height t1 of the convex portion and the concave step portion.

[0033] Furthermore, the fifteenth feature of this embodiment is a method for manufacturing an optical connector in which a convex step is provided on the end face where the insertion hole is provided during integral molding, and a concave step is provided on the end face opposite to the end face during integral molding, and the height t3 of the convex step and the height t4 of the concave step satisfy the relationship t3 = t4, and the height t1 of the convex step and the height t4 of the concave step satisfy the relationship t1 ≤ t3.

[0034] With these configurations or methods, in addition to positioning by the convex and concave portions, the convex step portion on the end face and the concave step portion on the end face (back side) engage with each other, further suppressing or preventing misalignment in the direction perpendicular to the connection direction of the optical connectors between multiple optical connectors. Therefore, compared to positioning by convex and concave portions alone, it is possible to further improve the positioning accuracy when connecting optical connectors, further increasing the alignment accuracy of each optical fiber end and further suppressing optical connection loss. Furthermore, by setting t3 = t4, no gap is created between the convex step portion on the end face and the concave step portion on the end face (back side) when they are engaged, enabling accurate positioning. Moreover, by setting t1 ≤ t3, it is prevented that the convex portion on the end face protrudes beyond the stepped surface of the convex step portion, avoiding the problem of the convex portion interfering with the polishing tool during polishing work on the optical fiber end face.

[0035] Examples of the present invention are described below, but the present invention is not limited to the following examples.

[0036] An embodiment of the present invention will be described below with reference to Figures 1 to 8. As shown in Figures 1 to 4, the optical connector 1 of this embodiment has an outer shape formed into a rectangular parallelepiped, and a plurality of protrusions (2a, 2b) and recesses (3a, 3b) are integrally molded. The protrusions (2a, 2b) are provided on the end face 1a of the optical connector 1, and the recesses (3a, 3b) are provided on the end face 1b of the optical connector 1. Furthermore, the optical connector 1 is integrally molded with insertion holes (4a, 4b, 4c, 4d) into which optical fibers are inserted and arranged.

[0037] The optical connector 1 is made of ceramic. Among ceramics, zirconia (ZrO2) is a particularly preferred material. Zirconia contains 3 mol% yttrium (Y) to achieve high toughness, high strength, and stability.

[0038] Two protrusions (2a, 2b) are formed on the left and right sides of the four insertion holes (4a, 4b, 4c, 4d), respectively. Similarly, two recesses (3a, 3b) are also formed on the left and right sides of the four insertion holes (4a, 4b, 4c, 4d), respectively. The protrusions (2a, 2b) are cylindrical in shape, and the recesses (3a, 3b) are circular stop-holes. Furthermore, the ends of the protrusions (2a, 2b) and the bottoms of the recesses (3a, 3b) are chamfered at a 45° angle.

[0039] As shown in Figure 2, the height t1 of the protrusions (2a, 2b) is 0.225 mm, the height t2 of the recesses (3a, 3b) is 0.26 mm, the diameter of the cylindrical portion of the protrusions (2a, 2b) is 0.45 mm, the diameter of the circular retaining hole portion of the recesses (3a, 3b) is 0.47 mm, the chamfer amount at height t1 of the protrusions (2a, 2b) is 0.08 mm, and the chamfer amount at height t2 of the recesses (3a, 3b) is 0.07 mm.

[0040] As described above, the convex portions (2a, 2b) are formed in a cylindrical shape, and the concave portions (3a, 3b) are formed in a circular stop-hole shape. The ends of the convex portions (2a, 2b) and the bottoms of the concave portions (3a, 3b) are chamfered at a 45° angle. However, as mentioned above, the heights t1 and t2, as well as the diameters of the cylindrical portion and the circular stop-hole portion, are slightly different.

[0041] Furthermore, the central axis of the recess 3a is positioned on the central axis ax1 of the convex portion 2a, and the convex portion 2a and the recess 3a are formed coaxially on each end face 1a or 1b. Also, the central axis of the recess 3b is positioned on the central axis ax2 of the convex portion 2b, and the convex portion 2b and the recess 3b are formed coaxially on each end face 1a or 1b.

[0042] Multiple (four) insertion holes (4a, 4b, 4c, 4d) are provided, and each insertion hole (4a, 4b, 4c, 4d) is formed to allow multiple optical fibers 5 to be arranged in a row (see Figures 5 and 6). The shape of each insertion hole (4a, 4b, 4c, 4d) is formed by a flat surface (4a1, 4b1, 4c1, 4d1) and multiple V-grooves (4a2, 4b2, 4c2, 4d2), as shown in Figures 1 to 6, respectively. From Figure 5, four optical fibers 5 can be inserted into each insertion hole (4a, 4b, 4c, 4d). Corresponding to the number of optical fibers 5 to be inserted, the number of V-grooves (4a2, 4b2, 4c2, 4d2) formed in each insertion hole (4a, 4b, 4c, 4d) is also four. Therefore, the total number of optical fibers 5 that can be inserted into the optical connector 1 is 16.

[0043] Each V-groove (4a2, 4b2, 4c2, 4d2) is formed by two planes (4a3, 4a3) with an opening angle of 120°, as shown by 4a2 in Figure 6. Furthermore, the bottom of V-groove 4a2, which consists of two planes (4a3, 4a3), is rounded. Each V-groove (4a2, 4b2, 4c2, 4d2) is formed parallel to each other and also parallel to the central axes ax1 and ax2. The bottom of the V-grooves (4a2, 4b2, 4c2, 4d2) does not necessarily have to be rounded.

[0044] As shown in Figures 5 and 6, one optical fiber 5 is inserted into each V-groove (4a2, 4b2, 4c2, 4d2) of each insertion hole (4a, 4b, 4c, 4d), so that the optical fiber 5 is in three-point contact with two planes, namely the flat surface (4a1, 4b1, 4c1, 4d1) and each V-groove (4a2, 4b2, 4c2, 4d2), and is supported at three points. As shown in Figure 5, the core central axes axc connecting the respective core centers of the 16 optical fibers 5 inserted into each V-groove (4a2, 4b2, 4c2, 4d2) are arranged in a single line. Furthermore, the optical fibers 5 inserted into each V-groove (4a2, 4b2, 4c2, 4d2) are each arranged parallel and straight with respect to the central axes (ax1, ax2) of the convex portions (2a, 2b) and the concave portions (3a, 3b).

[0045] For the optical fiber 5, for example, the cladding diameter, which is the outer diameter, is Φ125 μm (Φ0.125 mm). As shown in Figures 6 and 7, such optical fibers 5 are each arranged with a gap P of 0.001 mm or more and 0.124 mm or less. When a single-mode fiber (with a cladding diameter of Φ0.125 mm) was used, under the condition that the shape of the insertion hole is a combination of the flat surfaces (4a1, 4b1, 4c1, 4d1) and the V-grooves (4a2, 4b2, 4c2, 4d2), the gap P was measured by non-contact measurement based on an imaging method. As a result, it was confirmed that the gap P is 0.0014 mm or more and 0.00425 mm or less. This actually measured value falls within the numerical range of the gap P of 0.001 mm or more and 0.124 mm or less, and it was confirmed that a high-precision single-row array of optical fibers is realized.

[0046] As shown in Figure 5, the respective core centers of all optical fibers 5 are arranged on a line connecting the centers of the end portions of the two convex portions (2a, 2b). Similarly, the respective core centers of all optical fibers 5 are arranged on a line connecting the centers of the bottom portions of the two concave portions (3a, 3b).

[0047] Next, the integral molding process of the optical connector 1 will be described. First, a material for forming the optical connector 1 is prepared. As described above, the material is ceramic, particularly zirconia containing 3 mol% of yttria. The material is further mixed with an organic binder and kneaded by a kneader.

[0048] Since the integral molding of the optical connector 1 is performed by injection molding, a mold for injection molding is also prepared. By mold transfer, the cylindrical outer shape of the convex portions (2a, 2b), the circular retaining hole shape of the concave portions (3a, 3b), the chamfer shape at the ends of the convex portions (2a, 2b) and the bottom of the concave portions (3a, 3b), and the shapes of the four insertion holes (4a, 4b, 4c, 4d) are respectively formed by integral molding, so that the optical connector 1 is molded.

[0049] The material for forming the optical connector 1 is injected into the prepared mold.

[0050] Next, the mold is cooled after pressure holding to solidify the material.

[0051] Next, the integrally molded product is taken out from the mold, degreased and fired.

[0052] Next, polishing finishing is performed on the fired integrally molded product.

[0053] As shown in FIG. 8, the optical connector 1 uses both the end surface 1a provided with the convex portions (2a, 2b) and the end surface 1b provided with the concave portions (3a, 3b) as connection surfaces, and by fitting the convex portions (2a, 2b) into the concave portions (3a, 3b), a plurality of optical connectors (1, 1) can be optically connected all at once.

[0054] In addition, the optical connector 1 may be used alone, or may be used as a connector assembly in combination with another housing or the like not shown.

[0055] According to the above optical connector 1 and the manufacturing method of the optical connector 1, instead of the conventional guide pins, the convex portions (2a, 2b) and the concave portions (3a, 3b) are provided integrally on the optical connector 1 by integral molding, so that the fitting error that occurred when inserting the guide pin into the guide pin hole is suppressed or prevented. Therefore, accurate positioning between the optical connector 1 and the end portions of the optical fibers 5 can be achieved, and the optical connection loss in each optical fiber 5 can be suppressed. In addition, since there is no need to use guide pins, the number of parts is reduced.

[0056] Furthermore, by forming the protrusions (2a, 2b) in a cylindrical shape and the recesses (3a, 3b) in a circular stopper hole shape, and by chamfering the ends of the protrusions (2a, 2b), chipping and cracking are prevented during the fitting or removal process of the protrusions (2a, 2b) and recesses (3a, 3b) when connecting the optical connector 1. In addition, the fitting and removal processes of the protrusions (2a, 2b) and recesses (3a, 3b) become easier. Moreover, since cracking and chipping of the protrusions (2a, 2b) and recesses (3a, 3b) during the integral molding process can also be prevented, the integral molding process can be made even easier.

[0057] Furthermore, by using zirconia as the material for forming the optical connector 1, it becomes possible to suppress the occurrence of chipping in the integrally molded product.

[0058] Furthermore, multiple insertion holes (4a, 4b, 4c, 4d) for the optical fibers 5 are provided (four in this embodiment), allowing multiple optical fibers 5 to be arranged in a line using each insertion hole (4a, 4b, 4c, 4d). In addition, the shape of each insertion hole (4a, 4b, 4c, 4d) is formed with a flat surface (4a1, 4b1, 4c1, 4d1) and multiple V-grooves (4a2, 4b2, 4c2, 4d2). Moreover, by inserting one optical fiber 5 into each V-groove (4a2, 4b2, 4c2, 4d2), the optical fibers 5 are supported at three points, and the core central axes axc of each optical fiber 5 are arranged in a line. As a result, position management of each end of the optical fiber 5 becomes easy. Furthermore, by supporting the optical fiber 5 at three points, each optical fiber 5 can be securely held, making it possible to arrange the optical fibers 5 in a line with high precision while maintaining an extremely small pitch interval (i.e., gap P). Furthermore, by arranging each optical fiber 5 with a gap P of 0.001 mm or more and 0.124 mm or less, it becomes possible to arrange the optical fibers 5 in a single line with high precision even when the gap P is narrowed to a numerical range of 0.001 mm or more and 0.124 mm or less.

[0059] Furthermore, by aligning the core centers of each optical fiber 5 on the line connecting the centers of the protrusions (2a, 2b) and the line connecting the centers of the recesses (3a, 3b), each optical fiber 5 can be aligned to match the formation position of the protrusions (2a, 2b) or recesses (3a, 3b). Consequently, it becomes possible to improve the positioning accuracy of the ends of each optical fiber 5 and reduce or suppress optical connection loss.

[0060] The optical connector 1 can be modified in various ways; for example, the convex portions (2a, 2b) and concave portions (3a, 3b) may be provided separately on the end faces 1a and 1b, respectively, as shown in Figure 9. In this case, one convex portion and one concave portion are integrally molded coaxially. In Figure 9, the convex portion 2a and concave portion 3a are provided coaxially, as are the convex portion 2b and concave portion 3b. As shown in Figure 9, the convex portions (2a, 2b) and concave portions (3a, 3b) are provided alternately on the end faces 1a and 1b, making it possible to optically connect multiple optical fibers by facing the end faces 1a together.

[0061] Furthermore, the height t1 of the protrusions (2a, 2b) and the height t2 of the recesses (3a, 3b) are not limited to the values ​​in the embodiment described above, but can be set arbitrarily.

[0062] Furthermore, the shape of the convex parts (2a, 2b) can be changed to a spherical dome shape, a trapezoidal cone shape, a multi-tiered shape (a two-tiered cylindrical shape in Figure 10(C)), a shape with a D-cut, a polygonal prism shape such as a triangular prism or a square prism, a cross shape, a trapezoidal triangular pyramid (and other shapes such as a square pyramid), etc. The concave parts (3a, 3b) can also be formed as locking holes with the shape of these convex parts as recesses.

[0063] Furthermore, the convex and concave portions may be a combination of the various shapes described above.

[0064] In addition to combinations of planes (4a1, 4b1, 4c1, 4d1) and V-grooves (4a2, 4b2, 4c2, 4d2), the shapes of the insertion holes (4a, 4b, 4c, 4d) can also be, as shown in order in Figures 11(A) to (H), of the following shapes: a combination of V-grooves, a combination of arc-shaped grooves, a triangular hole with a row of independent holes into which each optical fiber is inserted, a hole combining a plane and an arc-shaped groove with a row of independent holes into which each optical fiber is inserted, a shape combining a plane and an arc-shaped groove, a circular hole with a row of independent holes into which each optical fiber is inserted, a hole combining V-grooves with a row of independent holes into which each optical fiber is inserted, and an arc-shaped hole with a row of independent holes into which each optical fiber is inserted.

[0065] The total number of optical fibers 5 inserted into the optical connector 1 is limited to 16 fibers (upper limit) and 4 fibers (lower limit) according to JIS C 6838 (2000). By setting the total number of optical fibers 5 to 4 or more and 16 or less, the optical connector 1 can function as a multi-core optical connector. Alternatively, all 16 optical fibers 5 may be arranged in a single insertion hole 4e, as shown in Figure 12. By setting the upper limit of the total number of optical fibers 5 to 16 fibers, it is possible to set the maximum number of optical fibers 5 within a range where deformation of the insertion holes (4a, 4b, 4c, 4d, 4e) due to integral molding can be suppressed or prevented. Therefore, bulging of the shape of the insertion holes (4a, 4b, 4c, 4d, 4e) and bending of the central part of the insertion holes (4a, 4b, 4c, 4d, 4e) can also be suppressed or prevented.

[0066] Alternatively, multiple insertion holes 4a may be formed in a matrix-like manner with intervals between them in the vertical and horizontal directions, as shown in Figure 13.

[0067] Furthermore, the material forming the optical connector 1 is not limited to ceramic or zirconia, but can be changed to resin, glass, or metal. However, as mentioned above, zirconia containing 3 mol% yttrium (Y) is most preferred in terms of toughness, strength, and stability.

[0068] Furthermore, as shown in Figures 14 and 15, as an example of a modification of the optical connector 1, an optical connector 6 may be adopted that has a convex step portion and a concave step portion on the end face and the end face (back side). Similar to the optical connector 1 described above, the optical connector 6 has convex portions (2a, 2b) on one end face and concave portions (3a, 3b) on the opposite end face, and also has insertion holes (4a, 4b, 4c, 4d). In addition to these, a convex step portion 6a is integrally molded on the end face 1a of the optical connector 6, and a concave step portion 6b is integrally molded on the end face 1b. The convex step portion 6a and the concave step portion 6b are formed in a lap joint shape that extends across the entire width along one side of the end face and the end face (back side).

[0069] As shown in Figures 14 and 15, the convex step portion 6a is a step portion formed integrally along the edge of the end face 1a, and consists of a step portion surface 6a1 and step portion side surfaces (6a2, 6a3). The height of the convex step portion 6a is t3. On the other hand, the concave step portion 6b is a step portion formed integrally along the edge of the end face 1b, and consists of a step portion surface 6b1 and step portion side surfaces (6b2, 6b3). The height of the concave step portion 6b is t4. The height t3 of the convex step portion 6a and the height t4 of the concave step portion 6b are set to satisfy the relationship t3 = t4. By setting t3 = t4, when the convex step portion 6a of the end face 1a and the concave step portion 6b of the end face 1b are fitted together, no gap is created between them, and accurate positioning is possible between multiple optical connectors 6.

[0070] Furthermore, the relationship t1 ≤ t3 holds between the height t1 of the protrusions (2a, 2b) and the height t3 of the convex step 6a. If t1 > t3, the protrusions (2a, 2b) will protrude beyond the step surface 6a1 of the convex step 6a at the end face 1a, which may cause interference between the protrusions (2a, 2b) and the polishing tool during the polishing of the optical fiber end face. This problem is prevented by setting t1 ≤ t3. Note that the minimum value of t1 within the range satisfying t1 ≤ t3 can be set arbitrarily.

[0071] When connecting multiple optical connectors 6, the convex step portion 6a on the end face 1a of one optical connector 6 fits into the concave step portion 6b on the end face 1b of the other optical connector 6. As a result, in addition to positioning by the convex portions (2a, 2b) and concave portions (3a, 3b), positioning by fitting the convex step portion 6a and concave step portion 6b functions simultaneously, further restricting misalignment in the direction perpendicular to the connection direction of the optical connectors 6. Therefore, by having multiple positioning mechanisms function complementaryly, it is possible to further improve the positioning accuracy when connecting the optical connectors 6, further enhancing the alignment accuracy of each optical fiber 5 end and further suppressing optical connection loss.

[0072] The heights t3 and t4 of the convex step portion 6a and the concave step portion 6b can be arbitrarily set within a range that satisfies the relationships t3 = t4 and t1 ≤ t3, and does not interfere with the formation positions of the convex portions (2a, 2b) and concave portions (3a, 3b) or the arrangement of the insertion holes (4a, 4b, 4c, 4d).

[0073] 1 Optical connector 1a End face of optical connector (convex side) 1b End face of optical connector (concave side) 2a, 2b Convex part 3a, 3b Concave part 4a, 4b, 4c, 4d, 4e Optical fiber insertion hole 4a1, 4b1, 4c1, 4d1 Plane of insertion hole 4a2, 4b2, 4c2, 4d2 Multiple V-grooves 4a3 Plane forming the V-grooves 5 Optical fiber 6 Optical connector with convex and concave stepped parts (modified example) 6a Convex stepped part of the end face 6a1 Step surface of the convex stepped part 6a2, 6a3 Side surface of the stepped part of the convex stepped part 6b Concave stepped part of the end face (back side) 6b1 Step surface of the concave stepped part 6b2, 6b3 Side surface of the stepped part of the concave stepped part ax1 Central axis of convex part 2a ax2 Central axis of convex part 2b axc: The central axis of each core of the optical fiber. t1: Height of the convex portion. t2: Height of the concave portion. t3: ​​Height of the convex step. t4: Height of the concave step. P: Gap between optical fibers inserted into the V groove.

Claims

1. An optical connector having insertion holes for arranging optical fibers in a single row, and having multiple protrusions and recesses integrally molded on each end face on the same axis.

2. The optical connector according to claim 1, wherein the convex portion is cylindrical, the recess is circular in shape, and the end of the convex portion is chamfered.

3. The optical connector according to claim 1, wherein the material forming the optical connector is zirconia.

4. The optical connector according to claim 1, wherein a plurality of insertion holes are provided, each of the insertion holes is capable of arranging a plurality of optical fibers in a row, the shape of each of the insertion holes is formed by a plane and a plurality of V-grooves, one optical fiber is inserted into each of the V-grooves and the optical fibers are supported at three points, and the core central axes of each of the optical fibers are arranged in a row.

5. The optical connector according to claim 4, wherein each of the optical fibers is arranged with a gap of 0.001 mm or more and 0.124 mm or less.

6. The optical connector according to claim 4, wherein the number of optical fibers arranged in each of the insertion holes is 4 or more and 16 or less.

7. The optical connector according to claim 1, wherein a convex step portion is integrally molded on the end face on which the insertion hole is provided, and a concave step portion is integrally molded on the end face opposite to the end face, the convex step portion and the concave step portion are interlocked, the height t3 of the convex step portion and the height t4 of the concave step portion satisfy the relationship t3 = t4, and the height t1 of the convex portion and the height t4 of the concave step portion satisfy the relationship t1 ≤ t3.

8. A method for manufacturing an optical connector, comprising providing an insertion hole for arranging optical fibers in a single row by integral molding, and providing a plurality of protrusions and recesses on each end face coaxially by integral molding.

9. The method for manufacturing an optical connector according to claim 8, wherein the integral molding is injection molding.

10. The method for manufacturing an optical connector according to claim 8, wherein the convex portion is formed into a cylindrical shape by integral molding, the concave portion is formed into a circular stopper hole shape by integral molding, and the end of the convex portion is further chamfered by integral molding.

11. The method for manufacturing an optical connector according to claim 8, wherein the material used to form the optical connector is zirconia.

12. A method for manufacturing an optical connector according to claim 8, wherein a plurality of insertion holes are provided, each of the insertion holes is capable of arranging a plurality of optical fibers in a row, the shape of each of the insertion holes is formed with a plane and a plurality of V-grooves, the optical fibers are supported at three points by inserting one optical fiber into each of the V-grooves, and the core central axes of the optical fibers are arranged in a row.

13. The method for manufacturing an optical connector according to claim 12, wherein each of the optical fibers is arranged with a gap of 0.001 mm or more and 0.124 mm or less.

14. The method for manufacturing an optical connector according to claim 12, wherein the number of optical fibers arranged in each insertion hole is 4 or more and 16 or less.

15. A method for manufacturing an optical connector according to claim 8, wherein a convex step is provided on the end face on which the insertion hole is provided by integral molding, and a concave step is provided on the end face opposite to the end face by integral molding, and the height t3 of the convex step and the height t4 of the concave step are molded to satisfy the relationship t3 = t4, and the height t1 of the convex step and the height t4 of the concave step are molded to satisfy the relationship t1 ≤ t3.

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