Optical connection device

Abstract

Provided is an optical connection device (10) with which the accuracy of alignment of optical fibers is high and which reduces non-uniform stress. This device includes: a plurality of V-groove pairs (11) formed side by side in a first direction; a plurality of lenses (12) formed corresponding to the V-groove pairs (11) and side by side in the first direction; a reflection surface (13) disposed on the opposite side of the V-groove pairs (11) with the lenses (12) interposed therebetween; and a light emission section (14) that crosses the reflection surface (13). The plurality of V-groove pairs (11), the plurality of lenses (12), and the reflection surface (13) are integrally formed. Each of the plurality of V-groove pairs (11) includes: a first V-groove (11u); and a second V-groove (11d) opposingly disposed in a second direction orthogonal to the first direction. The first and second V-grooves (11u, 11d) extend in a third direction orthogonal to the first and second directions. A plurality of optical fibers (20) are disposed in correspondence with the plurality of V-groove pairs (11) and between the first and second V-grooves (11u, 11d).

Description

Optical Connection Device

[0001] The present disclosure relates to optical connection devices.

[0002] In the field of optical communication technology, optical connection devices are known that optically connect a plurality of optical fibers to optical devices such as optical waveguides, light receiving elements, etc. For example, Patent Document 1 discloses an optical connection device that has a V-groove substrate formed with grooves in which the optical fibers are arranged, and a flat substrate that is arranged on the opposite side of the V-groove substrate with the optical fibers interposed therebetween, in order to improve the alignment accuracy of the optical fibers.

[0003] Japanese Patent Application Laid-Open No. 2005-181455

[0004] However, in the optical connection device described in Patent Document 1, the optical fiber is sandwiched between a V-groove substrate and a flat substrate, and contacts the V-groove substrate at two points while contacting the flat substrate at one point. Therefore, depending on the number of contact points, the stress applied to the optical fiber may increase.

[0005] An object of one aspect of the present disclosure is to provide an optical connecting device that has high alignment accuracy for optical fibers and reduces non-uniform stress applied to the optical fibers.

[0006] An optical connection device according to one aspect of the present disclosure includes a plurality of V-groove pairs formed side by side in a first direction and in which optical fibers are arranged, a plurality of lens portions formed side by side in the first direction corresponding to the plurality of V-groove pairs, a reflective surface arranged on the opposite side of the plurality of V-groove pairs with the plurality of lens portions interposed therebetween, and a light emitting portion intersecting the reflective surface, wherein the plurality of V-groove pairs, the plurality of lens portions, and the reflective surface are integrally formed, and each of the plurality of V-groove pairs includes a first V-groove and a second V-groove arranged opposite the first V-groove in a second direction perpendicular to the first direction, the first V-groove and the second V-groove extending in a third direction perpendicular to each of the first direction and the second direction, and the plurality of optical fibers are arranged between the first V-groove and the second V-groove corresponding to the plurality of V-groove pairs.

[0007] According to one aspect of the present disclosure, an optical connection device can be provided that has high alignment accuracy for optical fibers and reduces non-uniform stress applied to the optical fibers.

[0008] 1 is a schematic top view of an optical connection device according to an embodiment. FIG. 2 is a schematic front view of the optical connection device according to the embodiment, viewed from the end side. FIG. 3 is a schematic cross-sectional view of the line III-III in FIG. 1. FIG. 4 is a schematic diagram showing the behavior of light emitted from an optical fiber arranged in the optical connection device according to the embodiment. FIG. 5 is a schematic front view of the line V-V in FIG. 3. FIG. 6 is a schematic cross-sectional view of the line VI-VI in FIG. 3. FIG. 7 is a schematic cross-sectional view of an optical connection device according to a first example. FIG. 8 is a schematic cross-sectional view of an optical connection device according to a second example. FIG. 9 is a schematic cross-sectional view of an optical connection device according to a third example. FIG. 10 is a schematic cross-sectional view of an optical connection device according to a fourth example.

[0009] Hereinafter, embodiments for carrying out the present disclosure will be described in detail with reference to the drawings. However, the embodiments shown below are examples of optical connection devices for realizing the technical ideas of the embodiments of the present disclosure, and are not limited to the following. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. In each drawing, the same components are given the same reference numerals, and duplicate explanations will be omitted as appropriate.

[0010] In the drawings shown below, directions are represented using a Cartesian coordinate system having an X-axis, a Y-axis, and a Z-axis. The direction along the X-axis is the first direction X, the direction along the Y-axis is the third direction Y, and the direction along the Z-axis is the second direction Z. However, the above directional expressions merely describe the relationship between relative positions, orientations, directions, etc., and do not necessarily correspond to the relationship during use.

[0011] In the terms of this specification and claims, "orthogonal" may include a deviation of ±10 degrees or less from 90 degrees. Also, "parallel" may include a deviation of ±10 degrees or less from 0 degrees. "Disposed" is not limited to direct contact, but also includes indirect placement, for example, via another member.

[0012] [Embodiment] An optical connection device according to an embodiment will be described with reference to Fig. 1 to Fig. 6. Fig. 1 is a schematic top view of an optical connection device 10 according to an embodiment. Fig. 2 is a schematic front view of the optical connection device 10 as viewed from the end 16 side. Fig. 3 is a schematic cross-sectional view taken along line III-III in Fig. 1. Fig. 4 is a schematic diagram showing the behavior of light L emitted from an optical fiber 20 arranged in the optical connection device 10. Fig. 5 is a schematic front view taken along line V-V in Fig. 3. Fig. 6 is a schematic cross-sectional view taken along line VI-VI in Fig. 3.

[0013] The optical connection device 10 is a device used to optically connect a plurality of optical fibers to optical devices such as optical waveguides and light-receiving elements. Note that optical connection in the optical connection device 10 means that light emitted from a plurality of optical fibers is made incident on an optical device such as an optical waveguide or a light-receiving element via the optical connection device 10.

[0014] 1 to 3 , the optical connection device 10 includes a plurality of V-groove pairs 11 formed side by side in a first direction X and in which a plurality of optical fibers are arranged, and a plurality of lens portions 12 formed side by side in the first direction X corresponding to the plurality of V-groove pairs 11. The optical connection device 10 also includes a reflecting surface 13 arranged on the opposite side of the plurality of V-groove pairs 11 with the plurality of lens portions 12 interposed therebetween, and a light emitting portion 14 intersecting with the reflecting surface 13.

[0015] 1 to 3 , the optical connection device 10 includes an abutment portion 15 with which the light emission surfaces of the multiple optical fibers arranged in the multiple V-groove pairs 11 abut, an end portion 16 located on the opposite side of the optical connection device from the reflecting surface 13, a flat portion 17 formed around each of the multiple lens portions 12, and a bottom surface 19 connected to the end portion 16 and the light emission portion 14. The optical connection device 10 also has multiple through holes 18 that pass through between the abutment portion 15 and the flat portion 17 and correspond to the multiple lens portions 12. The abutment portion 15 and the flat portion 17 are flat surfaces that are parallel to each other.

[0016] The multiple V-groove pairs 11 are continuous groove structures that align multiple optical fibers so that the core axes of the multiple optical fibers are parallel to one another. The multiple lens portions 12 are lenses that couple divergent light emitted from the optical fibers arranged in the multiple V-groove pairs 11. The reflecting surface 13 is a surface that converts the optical path of the light coupled by the multiple lens portions 12 to an optical device such as an optical waveguide or a light receiving element that is arranged opposite the light emitting portion 14 outside the optical connection device 10. The light emitting portion 14 is a portion that emits the light L reflected by the reflecting surface 13 from the optical connection device 10 to the outside.

[0017] 3 and 4, the reflecting surface 13 and the light emitting portion 14 intersect continuously. However, the light emitting portion 14 may intersect discontinuously with the reflecting surface 13 with a portion other than the reflecting surface 13 and the light emitting portion 14 interposed between the reflecting surface 13 and the light emitting portion 14.

[0018] 1 and 2 , the multiple V-groove pairs 11 include four V-groove pairs 11. The multiple lens portions 12 include four lens portions 12 corresponding to the multiple V-groove pairs 11. However, the number of each of the multiple V-groove pairs 11 and the multiple lens portions 12 is not limited to four and can be changed as appropriate. In consideration of the relationship with the number of optical fibers to be optically connected, the number of each of the multiple V-groove pairs 11 and the multiple lens portions 12 is preferably a multiple of four. The four V-groove pairs 11 preferably have the same shape in order to make the core axes of the multiple optical fibers parallel to one another, and the four lens portions 12 preferably have the same shape in order to couple the light emitted from the optical fibers parallel to one another.

[0019] In this embodiment, the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 are integrally formed. Here, "integrally formed" means that at least the optical path portions of the light emitted from the multiple optical fibers arranged in the multiple V-groove pairs 11 are formed as the same member in the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13. From another perspective, as long as there is no interface in the optical path of the light emitted from the multiple optical fibers arranged in the multiple V-groove pairs 11 in the optical connection device 10, even if the multiple V-groove pairs 11, the multiple lens portions 12, and parts of the reflecting surface 13 are formed as separate members, this also falls under the category of "the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 being integrally formed."

[0020] Each of the multiple V-groove pairs 11 includes a first V-groove 11u and a second V-groove 11d arranged opposite the first V-groove 11u in a second direction Z perpendicular to the first direction X. The first V-groove 11u and the second V-groove 11d extend in a third direction Y perpendicular to each of the first direction X and the second direction Z.

[0021] 4, the plurality of optical fibers 20 are arranged between the first V groove 11u and the second V groove 11d in correspondence with the plurality of V-groove pairs 11. The plurality of lens portions 12 couple light L emitted from the plurality of optical fibers 20 arranged between the first V groove 11u and the second V groove 11d. The reflecting surface 13 reflects the light L coupled by the plurality of lens portions 12 toward the light emitting portion 14.

[0022] 4 , the optical fiber 20 includes a core 21, a cladding 22 disposed around the core 21, and a light emitting surface 23. As an example, the optical fiber 20 has an optical fiber diameter of 125 μm and a core diameter of 9 μm. The optical fiber 20 is disposed between the first V-groove 11u and the second V-groove 11d so that the light emitting surface 23 abuts against the abutment portion 15. The abutment of the light emitting surface 23 against the abutment portion 15 positions the optical fiber 20 at a predetermined position in the third direction Y.

[0023] 6, when the light emitting surface 23 abuts against the abutment portion 15, the optical fiber 20 contacts the first V-groove 11u at a first contact point C1 and a second contact point C2. The optical fiber 20 also contacts the second V-groove 11d at a third contact point C3 and a fourth contact point C4. The contact at the first contact point C1, the second contact point C2, the third contact point C3, and the fourth contact point C4 positions the optical fiber 20 at a predetermined position in each of the first direction X and the second direction Z.

[0024] 4, when the optical fiber 20 is disposed between the first V-groove 11u and the second V-groove 11d, light guided through the core 21 of the optical fiber 20 passes through the light exit surface 23 and exits the optical fiber 20. The light L exiting the optical fiber 20 propagates inside the through-hole 18 while diverging, and then enters the lens portion 12. The light L entering the lens portion 12 is converted into coupling light by the lens portion 12 and propagates inside the optical connection device 10 toward the reflecting surface 13. The light L reaching the reflecting surface 13 is reflected by the reflecting surface 13 toward the light exit portion 14.

[0025] The light L reflected by the reflecting surface 13 is emitted to the outside of the optical connection device 10 through the light emitting portion 14 and enters an optical device such as an optical waveguide or a light receiving element arranged opposite the light emitting portion 14. This results in optical connection between the optical fiber 20 and the optical device such as the optical waveguide or the light receiving element.

[0026] High-speed, large-capacity optical communications require the high-density integration of numerous optical fibers within a limited space. High-density integration of optical fibers requires a device that aligns multiple optical fibers and optically connects the aligned multiple optical fibers to optical devices such as optical waveguides and light-receiving elements. However, the core of an optical fiber is very thin, and low alignment accuracy of the optical fiber with optical devices such as optical waveguides and light-receiving elements results in high optical loss. Therefore, optical connection devices require high alignment accuracy.

[0027] For example, Patent Document 1 discloses an optical connection device having a V-groove substrate with a groove formed therein in which an optical fiber is arranged, and a flat substrate disposed on the opposite side of the V-groove substrate via the optical fiber, in order to improve the alignment accuracy of the optical fiber. However, in the optical connection device described in Patent Document 1, the optical fiber is sandwiched between the V-groove substrate and the flat substrate, and contacts the V-groove substrate at two points, while contacting the flat substrate at one point. As a result, uneven stress may be applied to the optical fiber depending on the number of contact points. When uneven stress is applied to the optical fiber, the optical characteristics of the light guided by the optical fiber change, affecting the performance of optical communication. For example, in a polarization-maintaining fiber, the extinction ratio changes due to uneven stress applied to the optical fiber. This affects the performance of optical communication.

[0028] In the optical connection device 10 according to this embodiment, the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 are integrally formed. As a result, the relative positional accuracy of the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 depends on the processing accuracy of the optical connection device 10, and positional deviation over time is unlikely to occur. As a result, the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 can be relatively positioned with higher accuracy than when they are not integrally formed, and the multiple optical fibers 20 aligned by the multiple V-groove pairs 11 can be aligned with high accuracy with respect to optical devices such as optical waveguides and light-receiving elements.

[0029] Furthermore, in the optical connection device 10 according to this embodiment, the multiple optical fibers 20 are arranged between the first V groove 11u and the second V groove 11d in correspondence with the multiple V-groove pairs 11. By arranging the multiple optical fibers 20 between the first V groove 11u and the second V groove 11d, the multiple optical fibers 20 can be aligned with high precision. Furthermore, the first V groove 11u contacts the corresponding optical fiber 20 at two points, and the second V groove 11d contacts the corresponding optical fiber 20 at two points. This results in the first V groove 11u and the second V groove 11d having the same number of contact points with the optical fiber 20, thereby reducing non-uniform stress applied to the optical fiber.

[0030] As described above, in this embodiment, it is possible to provide an optical connection device 10 that has high alignment accuracy of optical fibers and reduces non-uniform stress applied to the optical fibers.

[0031] Furthermore, in this embodiment, the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 are integrally formed, thereby miniaturizing the optical connection device 10. This makes it possible to meet the need for high-density integration of optical fibers and optical devices in high-speed, large-capacity optical communications. Furthermore, by aligning the multiple optical fibers 20 with optical devices such as optical waveguides and light-receiving elements with high precision, low-loss optical connections are achieved, reducing transmission loss in optical communications. In addition, the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 are integrally formed, which reduces the assembly process compared to when these are formed as separate components, thereby simplifying the manufacturing process of the optical connection device and facilitating its manufacture.

[0032] In this embodiment, the optical connection device 10 is preferably composed of a glass material having an average linear expansion coefficient of 10 ppm / °C (parts per million) or less. In this specification, "average linear expansion coefficient" refers to a value measured by the average rate of expansion per degree Celsius when heated in the range of 100 to 300°C. This reduces relative positional deviations of the multiple V-groove pairs 11, the multiple lens portions 12, and the reflecting surface 13 due to temperature fluctuations around the optical connection device 10, thereby improving the alignment accuracy of the multiple optical fibers 20 with optical devices such as optical waveguides and light receiving elements. However, the material constituting the optical connection device 10 may be a glass material having an average linear expansion coefficient greater than 10 ppm / °C, or may be a resin material. The glass material and resin material preferably have a light transmittance of 60% or more for light L. However, a portion of the optical connection device 10 may be composed of a light-blocking material such as a metal material.

[0033] The optical connection device 10, in which the plurality of V-groove pairs 11, the plurality of lens portions 12, and the reflective surface 13 are integrally formed, is manufactured by, for example, molding using a glass material. At least a portion of the surface of the optical connection device 10 may be appropriately provided with an anti-reflection film, an increased reflection film, a multilayer film, a metal film, a hard coat layer, or the like. Furthermore, a processing method other than molding may be appropriately used to manufacture the optical connection device 10. Processing methods other than molding include cutting, polishing, sintering, etching, and the like.

[0034] In this embodiment, as shown in Fig. 2, the first V groove 11u and the second V groove 11d in the V groove pair 11 are preferably arranged so that the open portions of the V grooves face each other in the third direction Y. In the example shown in Fig. 2, the first V groove 11u and the second V groove 11d have symmetrical shapes. Because the first V groove 11u and the second V groove 11d have symmetrical shapes, the contact position with the optical fiber 20 to be placed is symmetrical between the first V groove 11u and the second V groove 11d. This reduces non-uniform stress applied to the optical fiber 20.

[0035] The variation in the vertex-to-vertex distance P between adjacent first V-grooves 11u in the first direction X is preferably 5 μm or less, and more preferably 2 μm or less. The variation in the vertex-to-vertex distance P refers to the maximum deviation from the average value of the vertex-to-vertex distances, in other words, the maximum absolute value of the difference from the average value. As shown in FIG. 3 , the variation in the shortest distance D between the midpoint M of the line connecting the vertex of the first V-groove 11u and the vertex of the second V-groove 11d in the V-groove pair 11 and the surface of the lens portion 12 corresponding to the V-groove pair 11 is preferably 5 μm or less, and more preferably 2 μm or less. By satisfying these conditions, the multiple optical fibers 20 aligned by the multiple V-groove pairs 11 can be aligned with high precision to optical devices such as optical waveguides and light-receiving elements. As a result, optical connection with low optical loss is achieved, reducing transmission loss in optical communications.

[0036] Here, optical fibers may be manufactured so that the light exit surface of the optical fiber is not perpendicular to the axis along which the optical fiber extends, but is tilted at an angle slightly deviated from 90 degrees. Tilting the light exit surface with respect to the axis of the optical fiber reduces Fresnel reflection at the light exit surface of the optical fiber, thereby reducing transmission loss in optical communications. However, for example, if the light exit surface 23 of the optical fiber 20 is not perpendicular to the axis of the optical fiber 20 but is tilted at an angle slightly deviated from 90 degrees, when the light exit surface 23 of the optical fiber 20 abuts against the abutting portion 15, the axis of the optical fiber 20 will not be perpendicular to the flat surface of the abutting portion 15. This may result in the optical fiber 20 not being properly positioned between the first V-groove 11u and the second V-groove 11d, or the light exit surface 23 not contacting the entire flat surface of the abutting portion 15, thereby reducing the alignment accuracy of the optical fiber 20.

[0037] In this embodiment, as shown in Fig. 3, the first minimum distance Δ1 between the end 16 and the abutment portion 15 is preferably 0.05 mm or more and 3 mm or less. As shown in Figs. 3, 5, and 6, the angle θ1 formed by a line 111 connecting the vertex T11 of the first V groove 11u at the end 16 and the vertex T21 of the first V groove 11u at the abutment portion 15 and a normal line 160 to the end 16 is preferably 2 degrees or more and 10 degrees or less. Furthermore, the angle θ2 formed by a line 112 connecting the vertex T12 of the second V groove 11d at the end 16 and the vertex T22 of the second V groove 11d at the abutment portion 15 and a normal line to the end 16 is preferably 2 degrees or more and 10 degrees or less. In the multiple V-groove pairs 11, the distance H between the apex of the first V groove 11u and the apex of the second V groove 11d in the second direction Z becomes shorter as one moves from the end 16 toward the abutting portion 15. In the example shown in FIGS. 5 and 6 , the distance H2 between the apex of the first V groove 11u and the apex of the second V groove 11d in the second direction Z at the position of the abutting portion 15 is shorter than the distance H1 between the apex of the first V groove 11u and the apex of the second V groove 11d in the second direction Z at the position of the abutting portion 15. With the above configuration, even when the light emitting surface 23 is not perpendicular to the axis of the optical fiber 20 but is inclined at an angle slightly deviated from 90 degrees, it is possible to reduce the possibility of the optical fiber 20 being unable to be properly positioned between the first V groove 11u and the second V groove 11d or the light emitting surface 23 not coming into contact with the entire flat surface of the abutting portion 15. As a result, a decrease in the alignment accuracy of the optical fiber 20 is suppressed. In the example shown in Fig. 3, the angle θ1 and the angle θ2 are substantially the same, but the angle θ1 and the angle θ2 may be different. For convenience of explanation, the optical fiber 20 and the core 21 are shown in Fig. 6, but the optical fiber 20 and the core 21 are not shown in Fig. 5.

[0038] As shown in FIG. 4 , in this embodiment, the multiple optical fibers 20 are preferably arranged in the optical connection device 10 so that their light emitting surfaces 23 abut against the abutting portions 15. The lens portion 12 includes a convex surface that is convex on the side opposite to the side on which the reflecting surface 13 is located, with respect to the flat portion 17. The focal point F of the lens portion 12 is located within an imaginary plane S that includes the abutting portions 15. By abutting the light emitting surface 23 against the abutting portions 15, the distance between the light emitting surface 23 and the lens portion 12 is determined with high precision, and the core 21 at the light emitting surface 23 and the focal point F of the lens portion 12 substantially coincide with each other. As a result, the light L that is emitted from the core 21 and diverges is converted by the lens portion 12 into highly parallel coupled light. Because the light L is highly parallel coupled light, it is easier to control the light L. As a result, the light L can be incident on optical devices such as optical waveguides and light receiving elements with low optical loss, thereby reducing transmission loss in optical communications.

[0039] The convex surface of the lens portion 12 is, for example, a spherical surface. However, the convex surface of the lens portion 12 may be an aspherical surface such as a parabolic surface. Furthermore, the lens portion 12 is not limited to a convex surface and may include a concave surface, a Fresnel lens surface, a diffractive lens surface, etc. Furthermore, the optical connection device 10 does not necessarily have to have the abutting portion 15 and the flat portion 17. The focal point F of the lens portion 12 does not necessarily have to be located within the imaginary plane S that includes the abutting portion 15.

[0040] In the present embodiment, the second minimum distance Δ2 between the abutting portion 15 and the flat portion 17 is preferably 0.1 mm or more and 1 mm or less. By satisfying this condition, the light L emitted from the core 21 when the light emitting surface 23 is in contact with the abutting portion 15 can be collected with high efficiency by the lens portion 12, thereby increasing the coupling efficiency of the lens portion 12. Note that, from the viewpoint of increasing the parallelism of the light L coupled by the lens portion 12 and converted into coupled light, it is preferable to determine the focal length of the lens portion 12 in accordance with the second minimum distance Δ2 so that the focal point F of the lens portion 12 is located within the imaginary plane S.

[0041] In this embodiment, it is preferable that the surface roughness Ra of the lens portion 12 and the surface roughness Ra of the reflecting surface 13 are each 50 nm or less. By satisfying this condition, scattering of the light L incident on each of the lens portion 12 and the reflecting surface 13 is reduced, thereby reducing optical loss.

[0042] 3 and 4, the reflecting surface 13 is a surface that totally reflects the incident light L. However, the reflecting surface 13 is not limited to a totally reflecting surface, and may be a surface configured to include a multilayer film, a metal film, or the like. The angle of the reflecting surface 13 with respect to the lower surface 19 can be changed as appropriate depending on the specifications of the optical connection device 10, etc. However, when the reflecting surface 13 totally reflects the incident light L, it is preferable that the angle of the reflecting surface 13, for example, the angle of the reflecting surface 13 with respect to the lower surface 19, be determined so as to satisfy the total reflection condition for the incident light L.

[0043] 3, the light emitting portion 14 is formed to be inclined at a predetermined emitting portion angle δ with respect to the lower surface 19. The emitting portion angle δ can be changed as appropriate depending on the specifications of the optical connection device 10 and the shapes of optical devices such as optical waveguides and light receiving elements.

[0044] Examples Examples will be described below, but the present disclosure is not limited to these examples.

[0045] Examples will be described with reference to Figs. 7 to 10. Fig. 7 is a schematic cross-sectional view of an optical connecting device 10a according to a first example. Fig. 8 is a schematic cross-sectional view of an optical connecting device 10b according to a second example. Fig. 9 is a schematic cross-sectional view of an optical connecting device 10c according to a third example. Fig. 10 is a schematic cross-sectional view of an optical connecting device 10d according to a fourth example. Figs. 7 to 10 show cross sections corresponding to line III-III in Fig. 1. Table 1 shows the main specifications of the optical connecting devices according to Examples 1 to 4. Note that Examples 1 to 4 are all examples.

[0046]

[0047] (Example 1) The optical connection device 10a according to Example 1 differs from the optical connection device 10 according to the embodiment in that it does not have the abutment portion 15. In the example shown in Fig. 7, the through hole 18 is a tapered hole whose inner surface is formed at taper angles that are the same as the inclination angles θ1 and θ2 of the V-groove pair 11. However, the taper angles of the through hole 18 in the optical connection device 10a do not necessarily have to be the same as the angles θ1 and θ2.

[0048] Because the optical connection device 10a does not have an abutting portion 15, the optical fiber is inserted from the end portion 16 side and positioned in the third direction Y at a position where the light emitting surface of the optical fiber contacts the inner surface of the tapered through hole 18. In the optical connection device 10a, the first minimum distance Δ1 corresponds to the distance between the end portion 16 and the position where the light emitting surface of the optical fiber contacts the inner surface of the through hole 18. Furthermore, the second minimum distance Δ2 corresponds to the distance between the flat portion 17 and the position where the light emitting surface of the optical fiber contacts the inner surface of the through hole 18.

[0049] The optical connecting device 10a as described above can also provide the same effects as the optical connecting device 10 according to the embodiment.

[0050] (Example 2) The optical connection device 10b according to Example 2 differs from the optical connection device 10 according to the embodiment in that the V-groove pair 11 is not tilted at angles θ1 and θ2. In other words, in the optical connection device 10b, as shown in Figures 3, 5, and 6, the angle θ1 formed by a line 111 connecting the vertex T11 of the first V-groove 11u at the position of the end 16 and the vertex T21 of the first V-groove 11u at the position of the abutting portion 15, and a normal 160 to the end 16 is approximately 0 degrees. Also, in the optical connection device 10b, the angle θ2 formed by a line 112 connecting the vertex T12 of the second V-groove 11d at the position of the end 16 and the vertex T22 of the second V-groove 11d at the position of the abutting portion 15, and the normal 160 to the end 16 is approximately 0 degrees.

[0051] The optical connecting device 10b as described above can also provide the same effects as the optical connecting device 10 according to the embodiment.

[0052] (Example 3) The optical connecting device 10c according to Example 3 has the same shape as the optical connecting device 10 according to the embodiment, and specific numerical values ​​are applied to the lens diameter φ, first minimum interval Δ1, second minimum interval Δ2, angle θ1, and angle θ2 of the optical connecting device 10. The optical connecting device 10c can also achieve the same effects as the optical connecting device 10 according to the embodiment.

[0053] Example 4 An optical connecting device 10d according to Example 4 differs from the optical connecting device 10 according to the embodiment in that the reflecting surface 13 and the light emitting portion 14 each have a cube shape.

[0054] "The reflecting surface 13 has a cube shape" means that the surface of the first prism 130 arranged at the position of the reflecting surface 13 and the surface of the optical connecting device 10d arranged at the position of the reflecting surface 13 are bonded together, so that the reflecting surface 13 becomes part of the first prism 130. "The light emitting section 14 has a cube shape" means that the surface of the second prism 140 arranged at the position of the light emitting section 14 and the surface of the optical connecting device 10d arranged at the position of the light emitting section 14 are bonded together, so that the light emitting section 14 becomes part of the second prism 140.

[0055] The optical connecting device 10d as described above can also provide the same effects as the optical connecting device 10 according to the embodiment.

[0056] Although the preferred embodiments have been described in detail above, the present disclosure is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments of the present disclosure without departing from the scope of the claims.

[0057] All numbers such as ordinal numbers and quantities used in the description of the embodiments of the present disclosure are provided as examples to specifically explain the technology of the present disclosure, and the present disclosure is not limited to the illustrated numbers. Furthermore, the connection relationships between components are provided as examples to specifically explain the technology of the present disclosure, and do not limit the connection relationships that realize the functions of the present disclosure.

[0058] The optical connecting device according to the embodiment of the present disclosure has high alignment accuracy of the optical fiber and can reduce non-uniform stress on the optical fiber, and therefore can be suitably used in the field of high-speed, large-capacity optical communications. From the viewpoint of reducing non-uniform stress on the optical fiber and reducing changes in the extinction ratio, the optical connecting device according to the embodiment of the present disclosure can be particularly suitably used in optical communications using polarization-maintaining fiber. However, the optical connecting device according to the embodiment of the present disclosure is not limited to the optical communications field, and can also be suitably used in various instruments or devices that use optical fibers, such as sensors, measuring devices, or processing devices.

[0059] This application claims priority based on Japanese Patent Application No. 2024-118364, filed on July 24, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0060] 10, 10a, 10b, 10c, 10d Optical connecting device 11 V-groove pair 11u First V-groove 11d Second V-groove 111, 112 Straight line 12 Lens portion 13 Reflecting surface 130 First prism 14 Light emitting portion 140 Second prism 15 Abutting portion 16 End portion 160 Normal 17 Flat portion 18 Through hole 19 Lower surface 20 Optical fiber 21 Core 22 Cladding 23 Light emitting surface C1 First contact point C2 Second contact point C3 Third contact point C4 Fourth contact point D Shortest distance H, H1, H2 Distance L Light M Midpoint P Distance between vertices S Virtual plane T11, T12, T21, T22 Vertices θ1, θ2 Angle δ Exit angle Δ1 First minimum distance Δ2 Second minimum distance

Claims

1. An optical connection device comprising: a plurality of V-groove pairs formed side by side in a first direction, and in which a plurality of optical fibers are arranged; a plurality of lens portions formed side by side in the first direction corresponding to the plurality of V-groove pairs; a reflective surface arranged on the opposite side of the plurality of V-groove pairs with the plurality of lens portions interposed therebetween; and a light emitting portion intersecting the reflective surface, wherein the plurality of V-groove pairs, the plurality of lens portions, and the reflective surface are integrally formed; each of the plurality of V-groove pairs includes a first V-groove and a second V-groove arranged opposite the first V-groove in a second direction perpendicular to the first direction; the first V-groove and the second V-groove extend in a third direction perpendicular to each of the first and second directions; and the plurality of optical fibers are arranged between the first V-groove and the second V-groove, corresponding to the plurality of V-groove pairs.

2. The optical connection device according to claim 1, which is composed of a glass material having an average linear expansion coefficient of 10 ppm / °C or less.

3. An optical connection device as described in claim 1, wherein the variation in the distance between the vertices of adjacent first V-grooves in the first direction is 5 μm or less, and the variation in the shortest distance between the midpoint of a line connecting the vertex of the first V-groove and the vertex of the second V-groove in the V-groove pair and the surface of the lens portion corresponding to the V-groove pair is 5 μm or less.

4. The optical connection device according to claim 1, further comprising abutting portions where the light emitting surfaces of the plurality of optical fibers abut.

5. An optical connection device as described in claim 4, including an end located on the opposite side of the reflecting surface in the optical connection device, wherein a first minimum distance between the end and the abutment portion is 0.05 mm or more and 3 mm or less, an angle formed by a line connecting the vertex of the first V-groove at the end position and the vertex of the first V-groove at the abutment portion and a normal to the end is 2 degrees or more and 10 degrees or less, an angle formed by a line connecting the vertex of the second V-groove at the end position and the vertex of the second V-groove at the abutment portion and a normal to the end is 2 degrees or more and 10 degrees or less, and in the multiple V-groove pairs, the distance between the vertex of the first V-groove and the vertex of the second V-groove in the second direction becomes shorter as one moves from the end to the abutment portion.

6. An optical connection device according to claim 4, comprising a flat portion formed around each of the plurality of lens portions, a plurality of through holes penetrating between the abutting portion and the flat portion being provided corresponding to the plurality of lens portions, the lens portions comprising a convex surface that is convex on the side opposite to the side on which the reflecting surface is located, with the flat portion as a reference, and the focal point of the lens portions being located within an imaginary plane including the abutting portions.

7. The optical connection device according to claim 6, wherein the second minimum distance between the abutting portion and the flat portion is 0.1 mm or more and 1 mm or less.

8. The optical connection device according to claim 1, wherein the surface roughness Ra of the lens portion and the surface roughness Ra of the reflecting surface are each 50 nm or less.

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