Optical coupling component

Abstract

An optical coupling component (10) optically couples a plurality of optical fibers (61) and a photonic integrated circuit (7). The optical coupling component (10) comprises the plurality of optical fibers (61), an optical fiber holding component (4) which holds the plurality of optical fibers (61), and a lens array (5) which has a plurality of mirror lenses (53). The plurality of mirror lenses (53) each change the angle of an optical path between each of the plurality of optical fibers (61) and the photonic integrated circuit (7). The lens array (5) has a space structure in which a portion of the optical path from entry into to exit from the lens array (5) passes through the air. The optical fiber holding component (4) and the lens array (5) are formed independently from each other and are directly or indirectly connected to each other.

Description

Optical coupling component

[0001] This disclosure relates to an optical coupling component. This application claims priority under Japanese application No. 2024-193001, filed 1 November 2024, incorporating all the provisions contained herein.

[0002] Patent Document 1 discloses an optical coupling between an optical fiber and a grating coupler of a photonic integrated circuit. In this optical coupling, a stamped optical bench having a stamped structured reflective surface supports the optical fiber in an optically aligned position with respect to the structured reflective surface. The structured reflective surface redirects the light transmitted between the grating coupler and the optical fiber. Furthermore, the structured reflective surface has a reflective surface profile constructed to reshape the light in order to generate a mode field that matches the input and output of the optical fiber with the design angle of the grating coupler.

[0003] Patent Document 2 discloses a lens component. This lens component comprises a first lens assembly that optically connects a light-emitting element and a transmitting optical fiber, and a second lens assembly that optically connects a light-receiving element and a receiving optical fiber. The first lens assembly has a lens on the transmitting element side and a lens on the transmitting fiber side, and the second lens assembly has a lens on the receiving element side and a lens on the receiving fiber side.

[0004] Japanese Patent Publication No. 2017-516150 Japanese Patent Publication No. 2014-074795

[0005] An optical coupling component according to one embodiment of the present disclosure optically couples a plurality of optical fibers with an optical integrated circuit. The optical coupling component comprises a plurality of optical fibers, an optical fiber holding component for holding the plurality of optical fibers, and a lens array having a plurality of lens mirrors. Each of the plurality of lens mirrors changes the angle of the optical path between each of the plurality of optical fibers and the optical integrated circuit. The lens array has a spatial structure in which the portion of the optical path that enters the lens array and exits the lens array passes through the air. The optical fiber holding component and the lens array are formed independently of each other and are connected to each other directly or indirectly.

[0006] Figure 1 is a perspective view showing an electronic circuit module equipped with an optical coupling component according to an embodiment of the present disclosure. Figure 2 is an enlarged perspective view of the optical coupling component. Figure 3 is an exploded perspective view showing the main body and tape fiber of the optical coupling component. Figure 4 is a cross-sectional view along the line IV-IV in Figure 3. Figure 5 is a perspective view showing the appearance of the lens array. Figure 6 is a cross-sectional view of the lens array along the yz plane. Figure 7 is a cross-sectional view of the lens array along the yz plane. Figure 8 is a cross-sectional view of the lens array along the yz plane. Figure 9A is a diagram illustrating a modified optical fiber holding component and optical fiber. Figure 9B is a diagram illustrating a modified optical fiber holding component and optical fiber. Figure 10 is a cross-sectional view showing a modified main body. Figure 11 is a perspective view showing the appearance of the main body as a modified example. Figure 12 is a side view showing the appearance of the main body as a modified example. Figure 13 is a perspective view showing the appearance of the main body as a modified example. Figure 14 is a perspective view showing the appearance of the main body as a modified example. Figure 15 is a perspective view showing the appearance of the optical coupling component as a modified example. Figure 16 is a perspective view showing the appearance of the receptacle. Figure 17 is another perspective view showing the appearance of the receptacle. Figure 18 is a modified example, a perspective view showing the appearance of the main body. Figure 19 is a modified example, a side view showing the appearance of the main body. Figure 20 is a modified example, a perspective view showing the appearance of the receptacle. Figure 21 is a modified example, a perspective view showing the appearance of the main body. Figure 22 is a modified example, a side view showing the appearance of the main body.

[0007] For optical coupling of optical elements, it is desirable that the optical elements be precisely aligned. In the optical coupling described in Patent Document 1, the structured reflective surface and optical fiber alignment structure of the optical bench are integrally molded by precise stamping, thereby precisely aligning and supporting the optical fiber and the structured reflective surface. However, in the optical coupling described in Patent Document 1, when the mold of the optical bench is modified, the entire mold must be replaced, which increases manufacturing costs.

[0008] Furthermore, when using a resin lens as disclosed in Patent Document 2, the heat generated when high-power light is incident on the lens may cause deformation or a change in refractive index, potentially reducing the optical coupling efficiency.

[0009] This disclosure aims to provide an optical coupling component that can reduce manufacturing costs and improve optical coupling efficiency.

[0010] According to this disclosure, it is possible to provide an optical coupling component that can reduce manufacturing costs and improve optical coupling efficiency.

[0011] First, the contents of embodiments of the present disclosure will be listed and described. [1] An optical coupling component according to one embodiment of the present disclosure optically couples a plurality of optical fibers with an optical integrated circuit. The optical coupling component comprises a plurality of optical fibers, an optical fiber holding component that holds the plurality of optical fibers, and a lens array having a plurality of lens mirrors. Each of the plurality of lens mirrors changes the angle of the optical path between each of the plurality of optical fibers and the optical integrated circuit. The lens array has a spatial structure in which the portion of the optical path that enters the lens array and exits the lens array passes through the air. The optical fiber holding component and the lens array are formed independently of each other and are connected to each other directly or indirectly.

[0012] In the optical coupling component described in [1] above, the optical fiber holding component and the lens array are different components. This means that, for example, when manufacturing using a mold, even if the mold for either the optical fiber holding component or the lens array needs to be replaced when the mold is modified, the mold for the other component does not need to be replaced, thus reducing manufacturing costs. Furthermore, the light that propagates through the optical path from the lens array to the exit of the lens array passes through the air. This means that, for example, when high-power light is incident on the lens array, the lens array is less likely to generate heat. Therefore, deformation of the lens array or changes in refractive index due to thermal effects can be prevented, thereby improving optical coupling efficiency. Thus, the optical coupling component described in [1] above can reduce manufacturing costs and improve optical coupling efficiency.

[0013] [2] In the optical coupling component described in [1] above, the optical fiber holding component has a plurality of fiber holes, each of which fixes each of the plurality of optical fibers inserted into each of the plurality of fiber holes, and the tip surface of each of the plurality of optical fibers may be flush with one end surface of the optical fiber holding component. In this case, the positions of the tip surfaces of the plurality of optical fibers can be easily aligned. Therefore, it is possible to prevent the distance between the plurality of optical fibers and the plurality of lens mirrors from becoming uneven.

[0014] [3] In the optical coupling component described in [1] or [2] above, the optical fiber holding component and the lens array may be made of resin. In this case, the optical coupling component can be mass-produced while further reducing manufacturing costs.

[0015] [4] In any one of the optical coupling components described in [1] to [3] above, each of the multiple lens mirrors may have a metal film provided on at least a portion of the surface of the lens array. In this case, when high-power light is incident on the lens array, deformation of the lens array due to thermal effects can be prevented, thereby further improving the optical coupling efficiency.

[0016] [5] In the optical coupling components described in [1] to [4] above, each of the multiple lens mirrors may have an enhanced reflective coating provided on at least a portion of the surface of the lens array. In this case, the heat generated when high-power light is incident on each of the multiple lens mirrors can be reduced. Therefore, deformation of each of the multiple lens mirrors due to thermal effects can be prevented, and the optical coupling efficiency can be further improved.

[0017] [6] In any one of the optical coupling components from [1] to [5] above, the difference in the coefficient of thermal expansion between the optical fiber holding component and the lens array is 50 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the optical fiber holding component and the lens array can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0018] [7] In the optical coupling component described in [6] above, the difference in the coefficient of thermal expansion between the optical fiber holding component and the lens array is 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the optical fiber holding component and the lens array can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0019] [8] Any one of the optical coupling components from [1] to [7] above may have a protrusion provided on one of the optical fiber holding component and the lens array, and a recess provided on the other of the optical fiber holding component and the lens array, and may be equipped with a first positioning structure that determines the positional relationship between the optical fiber holding component and the lens array by inserting the protrusion into the recess. In this case, the tip faces of each of the multiple optical fibers can be precisely aligned with the lens array. Therefore, the optical coupling efficiency can be improved.

[0020] [9] Any one of the optical coupling components described in [1] to [7] above may include a second positioning structure that includes guide holes or guide grooves provided in both the optical fiber holding component and the lens array, and determines the positional relationship between the optical fiber holding component and the lens array by inserting the positioning component into the guide hole or pressing the positioning component into the guide groove. In this case, the tip faces of each of the multiple optical fibers can be precisely aligned with the lens array. Therefore, the optical coupling efficiency can be improved.

[0021]

[10] Any one of the optical coupling components from [1] to [9] above may further comprise an optical integrated circuit. The difference in the coefficient of thermal expansion between the lens array and the optical integrated circuit is 50 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array and the optical integrated circuit can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0022]

[11] In the optical coupling component described in

[10] above, the difference in the coefficient of linear expansion between the lens array and the optical integrated circuit is 20 × 10 －６The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array and the optical integrated circuit can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0023]

[12] Any one of the optical coupling components from [1] to [9] above may further comprise an optical integrated circuit. The optical fiber holding component may be bonded to the lens array. Either the optical fiber holding component or the lens array, or both, may be bonded to the optical integrated circuit. In this case, the multiple optical fibers held by the optical fiber holding component, the multiple lens mirrors of the lens array, and the optical integrated circuit can be precisely aligned. Therefore, the optical coupling efficiency can be improved.

[0024]

[13] Any one of the optical coupling components from [1] to

[12] above comprises a connector and a third positioning structure. The connector is fixed to the optical integrated circuit and connected to the lens array. The third positioning structure includes a guide hole provided on one of the connector and the lens array, and a guide pin provided on the other of the connector and the lens array, and the positional relationship between the lens array and the optical integrated circuit is determined by inserting the guide pin into the guide hole. In this case, the lens array and the optical integrated circuit can be aligned with high precision. Therefore, the optical coupling efficiency can be improved.

[0025]

[14] In the optical coupling component described in

[13] above, the difference in the coefficient of linear expansion between the connection portion and the optical integrated circuit is 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array and the optical integrated circuit can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0026] [Details of Embodiments of the Disclosure] Specific examples of the Disclosure will be described below with reference to the drawings. However, the Disclosure is not limited to these examples, and is intended to include all changes within the meaning and scope of the claims, as indicated by the claims. In the following description, the same elements in the drawings will be denoted by the same reference numerals, and redundant descriptions will be omitted.

[0027] Figure 1 is a perspective view showing an electronic circuit module 1 equipped with an optical coupling component according to an embodiment of this disclosure. This electronic circuit module 1 has a form known as CPO (Co-Packaged Optics) and is used in data centers or high-performance computing environments. In the electronic circuit module 1, a plurality of optical integrated circuits (photonic ICs) 7 are arranged near a large integrated circuit element 22, such as an ASIC (Application Specific Integrated Circuit) or GPU (Graphics Processing Unit), for example, surrounding the large integrated circuit element 22. This reduces power consumption and improves data transfer speed.

[0028] The electronic circuit module 1 comprises an electronic circuit board 2 and a plurality of optical coupling components 10. The electronic circuit board 2 has a wiring board 21 and a large integrated circuit element 22 mounted on the wiring board 21. The wiring board 21 has electrical pattern wiring formed on its surface and inside. The electrical pattern wiring electrically connects the large integrated circuit element 22 and the plurality of optical integrated circuits 7. The large integrated circuit element 22 transmits and receives electrical signals to and from the plurality of optical integrated circuits 7 via the pattern wiring.

[0029] Figure 2 is an enlarged perspective view of the optical coupling component 10. Each of the multiple optical coupling components 10 comprises a main body 3, a tape fiber 6 containing multiple optical fibers, and an optical integrated circuit 7. In each optical coupling component 10, the tape fiber 6 and the optical integrated circuit 7 are optically coupled to each other through the main body 3. The optical integrated circuit 7 is arranged on the surface of the wiring substrate 21 and fixed to the surface of the wiring substrate 21. The optical integrated circuit 7 is, for example, plate-shaped, and its thickness direction coincides with the thickness direction of the wiring substrate 21. The optical integrated circuit 7 is arranged between the large-scale integrated circuit element 22 and the edge of the wiring substrate 21. The optical integrated circuits 7 of the multiple optical coupling components 10 are aligned along the edge of the wiring substrate 21. The optical integrated circuit 7 has multiple optical semiconductor elements and multiple optical waveguides formed on the surface and inside the optical integrated circuit 7. The multiple optical semiconductor elements may include elements that convert optical signals into electrical signals, such as photodiodes. The multiple optical semiconductor elements may also include elements that convert electrical signals into optical signals, such as laser diodes. One optical semiconductor element converts the optical signals from each optical fiber of the tape fiber 6 into electrical signals and outputs these electrical signals to the large-scale integrated circuit element 22. Another optical semiconductor element converts the electrical signals from the large-scale integrated circuit element 22 into optical signals and outputs these optical signals to each optical fiber of the tape fiber 6 via an optical waveguide. The optical waveguide may include, for example, a grating coupler, which couples the optical signals emitted toward the main body 3 in the thickness direction of the optical integrated circuit 7, or the optical signals incident from the main body 3 into the optical integrated circuit 7, into the optical waveguide. The optical integrated circuit 7 may have a microlens in the grating coupler portion that collimates the optical signals emitted toward the main body 3.

[0030] Figure 3 is an exploded perspective view showing the main body 3 and tape fiber 6 of the optical coupling component 10. Figure 4 is a cross-sectional view along the line IV-IV in Figure 3. For ease of understanding, these figures show an xyz Cartesian coordinate system. As shown in these figures, the tape fiber 6 has a plurality of optical fibers 61 and a resin coating 62 that covers the plurality of optical fibers 61 together. The plurality of optical fibers 61 are arranged side by side in the x direction and each extends in the z direction. The tips of the plurality of optical fibers 61 are exposed from the resin coating 62. Each optical fiber 61 is, for example, a single-mode fiber. The numerical aperture (NA) of the tip face of each optical fiber 61 is, for example, 0.10.

[0031] The main body 3 comprises an optical fiber holding component 4 and a lens array 5. The optical fiber holding component 4 and the lens array 5 are formed independently of each other and are connected to each other directly or indirectly. The optical fiber holding component 4 and the lens array 5 are made of, for example, resin. The optical fiber holding component 4 is, for example, an MT ferrule. The difference in the coefficient of thermal expansion between the optical fiber holding component 4 and the lens array 5 is, for example, 50 × 10⁻⁶. －６ [ / °C] or lower, or 20 × 10 －６ The temperature is below [ / °C]. In the embodiment, the optical fiber holding component 4 and the lens array 5 are made of the same resin material. The constituent material of the optical fiber holding component 4 and the lens array 5 is, for example, polyphenylene sulfide (PPS), which is a resin material having a low coefficient of thermal expansion.

[0032] The optical fiber holding component 4 and the lens array 5 have a shape such as a substantially rectangular parallelepiped shape. The optical fiber holding component 4 in the illustrated example has a front end face 4a, a bottom face 4b, an upper face 4c, a rear end face 4d, side faces 4e, and side faces 4f. The lens array 5 in the illustrated example has a rear end face 5a, a bottom face 5b, an upper face 5c, a front end face 5d, side faces 5e, and side faces 5f. The front end face 4a and the rear end face 4d extend along the xy plane and face each other in the z direction. The rear end face 5a and the front end face 5d extend along the xy plane and face each other in the z direction. The bottom face 4b and the upper face 4c extend along the xz plane and face each other in the y direction. The bottom face 5b and the upper face 5c extend along the xz plane and face each other in the y direction. The side faces 4e and the side faces 4f extend along the yz plane and face each other in the x direction. The side faces 5e and the side faces 5f extend along the yz plane and face each other in the x direction.

[0033] The front end face 4a of the optical fiber holding component 4 and the rear end face 5a of the lens array 5 are adhesively fixed to each other. The bottom face 4b of the optical fiber holding component 4 and the bottom face 5b of the lens array 5 face the optical integrated circuit 7 (see FIG. 2). One or both of the bottom face 4b of the optical fiber holding component 4 and the bottom face 5b of the lens array 5 are adhesively fixed to the optical integrated circuit 7. In one example, the bottom face 4b and the bottom face 5b are flush with each other. The difference in the linear expansion coefficients between the lens array 5 and the optical integrated circuit 7 is, for example, 50×10 －６ [ / °C] or less, or 20×10 －６ [ / °C] or less.

[0034] The optical fiber holding component 4 holds the tape fiber 6 and the multiple optical fibers 61 exposed from the tape fiber 6. The optical fiber holding component 4 has multiple fiber holes 41 and a single fiber hole 42. Each fiber hole 41 reaches the front end surface 4a of the optical fiber holding component 4. Each fiber hole 41 fixes each optical fiber 61 exposed from the tape fiber 6 that is inserted into each fiber hole 41. In the assembly process of the optical coupling component 10, after each optical fiber 61 is inserted into each fiber hole 41, the tip surface of each optical fiber 61 is polished together with the front end surface 4a of the optical fiber holding component 4. As a result, the tip surface of each optical fiber 61 is flush with the front end surface 4a. The single fiber hole 42 is formed between the multiple fiber holes 41 and the rear end surface 4d and communicates with the multiple fiber holes 41. The single fiber hole 42 fixes the resin coating 62 inserted into the single fiber hole 42. The tip and front end faces 4a of each optical fiber 61 are slightly inclined with respect to the z-direction, i.e., the plane perpendicular to the optical axis direction of each optical fiber 61 (the xy-plane). This prevents Fresnel reflection at the tip face of each optical fiber 61. In line with the inclination of the front end face 4a, the rear end face 5a of the lens array 5 is also slightly inclined with respect to the plane perpendicular to the optical axis direction of each optical fiber 61 (the xy-plane). In one example, the front end face 4a and the rear end face 5a are parallel to each other.

[0035] Figure 5 is a perspective view showing the external appearance of the lens array 5. As shown in Figures 4 and 5, the lens array 5 has a spatial structure 51. The spatial structure 51 is a recess formed in the substantially rectangular parallelepiped lens array 5, and its interior is a space occupied by air. The spatial structure 51 is aligned with the tip surface of each optical fiber 61 in the z direction, that is, in the optical axis direction of each optical fiber 61. The spatial structure 51 faces the rear end surface 5a and also faces the bottom surface 5b. As a result, the portion of the optical path L between the tip surface of each optical fiber 61 and the optical integrated circuit 7 (see Figure 2) that enters the lens array 5 and exits the lens array 5 passes through the air inside the spatial structure 51.

[0036] The lens array 5 further has a light reflecting surface 52. The light reflecting surface 52 is a part of the inner surface of the spatial structure 51 and forms the spatial structure 51. The light reflecting surface 52 is aligned with the tip surfaces of the respective optical fibers 61 in the z direction, that is, the optical axis direction of each optical fiber 61. The light reflecting surface 52 is inclined with respect to both the z direction and the y direction and extends along the x direction.

[0037] As shown in FIG. 5, the lens array 5 further has a plurality of lens mirrors 53 formed on the light reflecting surface 52. The plurality of lens mirrors 53 are arranged along the x direction. Each lens mirror 53 is optically coupled to each optical fiber 61 and the optical integrated circuit 7 and changes the angle of the optical path L between each optical fiber 61 and the optical integrated circuit 7. In addition, each lens mirror 53 condenses the parallel light emitted from the optical integrated circuit 7 toward the tip surface of each optical fiber 61, or collimates the diffused light emitted from the tip surface of each optical fiber 61 toward the optical integrated circuit 7. The angle formed by the optical path L between each optical fiber 61 and each lens mirror 53 and the optical path L between the optical integrated circuit 7 and each lens mirror 53 is, for example, 70 degrees or more and 110 degrees or less. The distance from the tip surface of each optical fiber 61 to each lens mirror 53 is, for example, 200 μm. Each lens mirror 53 generates a mode field similar to the mode field of the optical fiber 61.

[0038] FIGS. 6, 7, and 8 are cross-sectional views along the yz plane of the lens array 5. The light reflecting surface 52 has a plurality of concave surfaces (lens surfaces) 52a. The plurality of concave surfaces 52a are arranged along the x direction. Each concave surface 52a serves as each lens mirror 53. Each concave surface 52a is substantially spherical. The radius of curvature in the x direction of each concave surface 52a is, for example, 0.2 mm or more and 0.4 mm or less. The radius of curvature in the y direction of each concave surface 52a is, for example, 0.6 mm or more and 0.8 mm or less.

[0039] In the example shown in FIG. 6, the lens array 5 further has a metal film 54 formed on the light reflection surface 52. The metal film 54 is provided on at least a part of the surface of the lens array 5 that includes a plurality of concave surfaces 52a, and in the illustrated example, it is provided only on the entire surface on the light reflection surface 52. The metal film 54 may be provided only on the plurality of concave surfaces 52a. That is, each lens mirror 53 has the metal film 54. In the example shown in FIG. 7, the lens array 5 further has an antireflection film 55 formed on the light reflection surface 52. The antireflection film 55 is provided on at least a part of the surface of the lens array 5 that includes a plurality of concave surfaces 52a, and in the illustrated example, it is provided only on the entire surface on the light reflection surface 52. The antireflection film 55 may be provided only on the plurality of concave surfaces 52a. That is, each lens mirror 53 has the antireflection film 55. As shown in FIG. 8, the antireflection film 55 may be formed on the metal film 54.

[0040] The metal film 54 is a film made of a metal material such as silver (Ag). The antireflection film 55 is a dielectric multilayer film in which a low refractive index layer such as silicon oxide and a high refractive index layer such as titanium oxide are alternately laminated. The light reflectivity of the antireflection film 55 is, for example, 90% or more. The metal film 54 or the antireflection film 55 is formed, for example, by vacuum deposition or the like on a plurality of concave surfaces 52a. The spatial structure 51 of the lens array 5 has an open shape in which there are no structures in the direction perpendicular to the light reflection surface 52, which is the deposition surface, in order to facilitate the vacuum deposition.

[0041] The effects obtained by the optical coupling component 10 according to this embodiment, which has the above configuration, will now be described. In the optical coupling component 10 of this embodiment, the optical fiber holding component 4 and the lens array 5 are different components. As a result, for example, when manufacturing using a mold, even if the mold for one of the optical fiber holding component 4 or the lens array 5 is replaced when the mold is modified, the other mold does not need to be replaced, thus reducing manufacturing costs. In addition, the width of each lens mirror 53 in the x direction can be widened to the same extent as the arrangement spacing of the optical fibers 61. Therefore, it becomes possible to design a lens that can achieve high coupling efficiency. Furthermore, in this embodiment, the distance from the tip surface of the optical fiber 61 to the lens mirror 53 is determined by the distance from the rear end surface 5a of the lens array 5 to the lens mirror 53. As a result, the variation in the distance between the tip surface of the optical fiber 61 and the lens mirror 53 that occurs when mounting the optical fiber 61 can be easily reduced.

[0042] Furthermore, in this embodiment, the light propagating through the optical path L from the moment it enters the lens array 5 until it exits the lens array 5 passes through the air and does not pass through the interior of the material forming the lens array 5. As a result, for example, when high-power light enters the lens array 5, the lens array 5 is less likely to generate heat. Therefore, deformation or changes in refractive index of the lens array 5 due to thermal effects can be prevented, thereby improving the optical coupling efficiency. Consequently, the optical coupling component 10 of this embodiment can reduce manufacturing costs and improve optical coupling efficiency.

[0043] Furthermore, the optical coupling described in Patent Document 1 is formed by precisely punching out a malleable metal body. In this case, aligning the optical fibers in two or more rows limits the design freedom of the structured reflective surface. In contrast, in this embodiment, the optical fiber holding component 4 has the function of aligning the optical fibers 61, while the lens array 5 does not have the function of aligning the optical fibers 61. Therefore, the design freedom of the multiple lens mirrors 53 can be greatly increased.

[0044] As in this embodiment, each fiber hole 41 fixes each optical fiber 61 inserted into each fiber hole 41, and the tip surface of each optical fiber 61 may be flush with the front end surface 4a of the optical fiber holding component 4. In this case, the positions of the tip surfaces of multiple optical fibers 61 can be easily aligned. Therefore, it is possible to prevent the distance between multiple optical fibers 61 and multiple lens mirrors 53 from becoming uneven. Furthermore, compared to a method of positioning by butting the tip surface of each optical fiber, such as the optical coupling described in Patent Document 1, the mounting of the optical fibers 61 becomes easier.

[0045] As in this embodiment, the optical fiber holding component 4 and the lens array 5 may be made of resin. In this case, compared to a metal optical coupler like the one described in Patent Document 1, the optical coupling component 10 can be mass-produced while further reducing manufacturing costs.

[0046] As in this embodiment, each of the multiple lens mirrors 53 may have a metal film 54 or an enhanced reflective film 55 provided on at least a portion of the surface of the lens array 5. In this case, when high-power light is incident on the lens array 5, deformation of the lens array 5 due to thermal effects can be prevented, thereby further improving the optical coupling efficiency.

[0047] As in this embodiment, each of the multiple lens mirrors 53 may further have an enhanced reflective film 55 provided on the metal film 54. In this case, the heat generated when high-power light is incident on each of the multiple lens mirrors 53 can be reduced. Therefore, deformation of each of the multiple lens mirrors 53 due to thermal effects can be prevented, and the optical coupling efficiency can be further improved.

[0048] As mentioned above, the difference in the coefficient of thermal expansion between the optical fiber holding component 4 and the lens array 5 is 50 × 10 －６ [ / °C] or lower, or 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the optical fiber holding component 4 and the lens array 5 can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0049] As in this embodiment, the difference in the coefficient of thermal expansion between the lens array 5 and the optical integrated circuit 7 is 50 × 10 －６ [ / °C] or lower, or 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array 5 and the optical integrated circuit 7 can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0050] As in this embodiment, the optical fiber holding component 4 may be bonded to the lens array 5. Either the optical fiber holding component 4 or the lens array 5, or both, may be bonded to the optical integrated circuit 7. In this case, the multiple optical fibers 61 held by the optical fiber holding component 4, the multiple lens mirrors 53 of the lens array 5, and the optical integrated circuit 7 can be precisely aligned. Therefore, the optical coupling efficiency can be improved.

[0051] [First Modified Example] Figures 9A and 9B are diagrams illustrating modified examples of the optical fiber holding component 4 and the optical fiber 61. In the above embodiment, the optical fiber 61 is arranged in a single row along the x-direction in the optical fiber holding component 4 (Figure 9A), but the optical fiber 61 may be arranged in two rows (Figure 9B), or in three or more rows. In that case, the number of lens mirrors 53 of the lens array 5 is also arranged in a number of rows corresponding to the number of rows of optical fiber 61. The number of optical fiber 61 per row is, for example, 40 or less.

[0052] [Second Modification] Figure 10 is a cross-sectional view showing a modified version of the main body 3. In the above embodiment, the front end surface 4a and the rear end surface 5a are inclined with respect to a plane (xy plane) perpendicular to the optical axis direction of each optical fiber 61. However, if Fresnel reflection is acceptable, the front end surface 4a and the rear end surface 5a may be aligned with a plane (xy plane) perpendicular to the optical axis direction of each optical fiber 61, as shown in Figure 10. In this case, the tip surface of each optical fiber 61, which is polished together with the front end surface 4a, will also be aligned with a plane perpendicular to the optical axis direction of each optical fiber 61.

[0053] [Third Modified Example] Figure 11 is a perspective view showing the external appearance of the main body 3A as a modified example of the main body 3. Figure 12 is a side view showing the external appearance of the main body 3A. In this modified example, the main body 3A includes an optical fiber holding component 4A and a lens array 5A instead of the optical fiber holding component 4 and lens array 5 of the above embodiment. One of the optical fiber holding component 4A and the lens array 5A (the lens array 5A in the illustrated example) is provided with a pair of protrusions 56 (only one protrusion 56 is shown in the figure). The other of the optical fiber holding component 4A and the lens array 5A (the optical fiber holding component 4A in the illustrated example) is provided with a pair of recesses 43 (only one recess 43 is shown in the figure). Note that the other configurations, excluding the protrusions 56 and recesses 43, are the same as in the above embodiment.

[0054] The protrusions 56 and recesses 43 constitute a first positioning structure C1 that determines the positional relationship between the optical fiber holding component 4A and the lens array 5A by inserting the protrusions 56 into the recesses 43. The protrusions 56 project from the rear end surface 5a toward the optical fiber holding component 4A. In the illustrated example, one of the pair of protrusions 56 includes a side surface 5e, and the other of the pair of protrusions 56 includes a side surface 5f. The recesses 43 are formed on the front end surface 4a. In the illustrated example, one of the pair of recesses 43 is formed along the side surface 4e, and the other of the pair of recesses 43 is formed along the side surface 4f.

[0055] As shown in this modified example, the optical coupling component 10 may have a protrusion 56 provided on one of the optical fiber holding component 4A and the lens array 5A, and a recess 43 provided on the other of the optical fiber holding component 4A and the lens array 5A, and may include a first positioning structure C1 that determines the positional relationship between the optical fiber holding component 4A and the lens array 5A by inserting the protrusion 56 into the recess 43. In this case, the tip surfaces of each of the multiple optical fibers 61 and the lens array 5A can be precisely aligned. Therefore, the optical coupling efficiency can be improved.

[0056] [Fourth Modification] Figure 13 is a perspective view showing the external appearance of the main body 3B as a modification of the main body 3. In this modification, the main body 3B includes an optical fiber holding component 4B and a lens array 5B instead of the optical fiber holding component 4 and lens array 5 of the above embodiment. In addition to the configuration of the optical fiber holding component 4 of the above embodiment, the optical fiber holding component 4B has a pair of guide grooves 44a and 44b. One guide groove 44a is formed on the side surface 4e and extends along the z direction. The other guide groove 44b is formed on the side surface 4f and extends along the z direction. The shape of each guide groove 44a and 44b in a cross section perpendicular to the direction of extension is, for example, an arc shape.

[0057] Lens array 5B has a pair of guide grooves 57a and 57b in addition to the configuration of lens array 5 of the embodiment described above. One guide groove 57a is formed on side surface 5e and extends along the z direction. The other guide groove 57b is formed on side surface 5f and extends along the z direction. The shape of each guide groove 57a and 57b in a cross section perpendicular to the direction of extension is, for example, an arc shape. The guide groove 57a formed on side surface 5e is connected to the guide groove 44a formed on side surface 4e. The guide groove 57b formed on side surface 5f is connected to the guide groove 44b formed on side surface 4f.

[0058] Guide grooves 44a, 44b and guide grooves 57a, 57b are second positioning structures C2A that determine the positional relationship between the optical fiber holding component 4B and the lens array 5B by pressing with positioning components. Specifically, a common positioning component (not shown) extending in the z direction is placed in guide grooves 44a and 57a, and this positioning component presses the optical fiber holding component 4B and the lens array 5B from one side. Another common positioning component (not shown) extending in the z direction is placed in guide grooves 44b and 57b, and this positioning component presses the optical fiber holding component 4B and the lens array 5B from the other side. This enables the relative positioning of the optical fiber holding component 4B and the lens array 5B.

[0059] As shown in this modified example, the optical coupling component 10 may include a second positioning structure C2A that determines the positional relationship between the optical fiber holding component 4B and the lens array 5B by pressing the positioning component against the guide grooves 44a, 44b and guide grooves 57a, 57b. In this case, the tip surfaces of each of the multiple optical fibers 61 can be precisely aligned with the lens array 5B. Therefore, the optical coupling efficiency can be improved.

[0060] [Fifth Modification] Figure 14 is a perspective view showing the external appearance of the main body 3C as a modification of the main body 3. In this modification, the main body 3C includes an optical fiber holding component 4C and a lens array 5C instead of the optical fiber holding component 4 and lens array 5 of the above embodiment. The optical fiber holding component 4C has a pair of guide holes 45a and 45b in addition to the configuration of the optical fiber holding component 4 of the above embodiment. One guide hole 45a is formed between the side surface 4e and the fiber hole 41 and single fiber hole 42, extends along the z direction, and penetrates the optical fiber holding component 4C from the rear end surface 4d to the front end surface 4a. The other guide hole 45b is formed between the side surface 4f and the fiber hole 41 and single fiber hole 42, extends along the z direction, and penetrates the optical fiber holding component 4C from the rear end surface 4d to the front end surface 4a. The shape of each guide hole 45a and 45b in a cross section perpendicular to the extending direction is, for example, circular.

[0061] The lens array 5C has a pair of guide holes 58a and 58b in addition to the configuration of the lens array 5 of the embodiment described above. One guide hole 58a is formed near the side surface 5e, extends along the z direction, and penetrates the lens array 5C from the rear end surface 5a to the front end surface 5d. The other guide hole 58b is formed near the side surface 5f, extends along the z direction, and penetrates the lens array 5C from the rear end surface 5a to the front end surface 5d. The shape of each guide hole 58a and 58b in a cross-section perpendicular to the direction of extension is, for example, circular. Guide hole 58a communicates with guide hole 45a. Guide hole 58b communicates with guide hole 45b.

[0062] Guide holes 45a, 45b and guide holes 58a, 58b are a second positioning structure C2B that determines the positional relationship between the optical fiber holding component 4C and the lens array 5C by inserting guide pins 8 as positioning components. Specifically, guide pins 8 extending in the z direction are inserted into guide holes 45a and 58a and guide holes 45b and 58b. This enables the relative positioning of the optical fiber holding component 4C and the lens array 5C. The guide pins 8 are made of metal, for example.

[0063] As shown in this modified example, the optical coupling component 10 may include a second positioning structure C2B that determines the positional relationship between the optical fiber holding component 4C and the lens array 5C by inserting guide pins 8 into guide holes 45a, 45b and guide holes 58a, 58b. In this case, the tip surfaces of each of the multiple optical fibers 61 can be precisely aligned with the lens array 5C. Therefore, the optical coupling efficiency can be improved. [Sixth Modified Example]

[0064] Figure 15 is a perspective view showing the appearance of an optical coupling component 10A as a modified example of the optical coupling component 10. Figure 16 is a perspective view showing the appearance of the receptacle 9. Figure 17 is another perspective view showing the appearance of the receptacle 9. Figure 18 is a perspective view showing the appearance of the main body 3D as a modified example of the main body 3. Figure 19 is a side view showing the appearance of the main body 3D as a modified example of the main body 3. The optical coupling component 10A in this modified example comprises a receptacle 9, a main body 3D instead of the main body 3 of the above embodiment, and a third positioning structure C3A. The main body 3D has a lens array 5D instead of the lens array 5 of the above embodiment.

[0065] The receptacle 9 is a connector fixed to the optical integrated circuit 7 and connected to the lens array 5D. The receptacle 9 is fixed to the optical integrated circuit 7 by being bonded to it. The receptacle 9 has a base plate portion 91 and vertical wall portions 92 provided on the side surface of the base plate portion 91. The difference in the coefficient of linear expansion between the receptacle 9 and the optical integrated circuit 7 is, for example, 1.0 × 10⁻⁶. －６ [ / °C] or higher, 20 × 10 －６ It is below [ / ℃].

[0066] The base plate portion 91 is rectangular in plan view. An optical aperture 93 is provided in the base plate portion 91. The aperture 93 is rectangular in plan view. The lens array 5D is optically coupled to the optical integrated circuit 7 through the aperture 93. Light reflected by the lens array 5D enters the optical integrated circuit 7 through the aperture 93. Light emitted from the optical integrated circuit 7 enters the lens array 5D through the aperture 93. The base plate portion 91 may have a transparent member instead of the aperture 93. Alternatively, the entire base plate portion 91 may be made of a transparent member, regardless of the presence or absence of the aperture 93.

[0067] The bottom plate portion 91 is provided with a pair of guide pins 94a and 94b. The vertical wall portion 92 includes a pair of side wall portions 92a and 92b that are provided on the side surface of the bottom plate portion 91 intersecting the z-direction and facing each other, and a back wall 92c that is provided on the side surface of the bottom plate portion 91 intersecting the x-direction and connecting one end of each side wall portion 92a and 92b. The guide pin 94a is provided between the side wall portions 92a and 92b, at a position on the upper surface 91a of the bottom plate portion 91 closer to the side wall portion 92b. The guide pin 94b is provided between the side wall portions 92a and 92b, at a position on the upper surface 91a of the bottom plate portion 91 closer to the side wall portion 92b. The back wall 92c is provided on the side surface of the bottom plate portion 91 that is closer to the pair of guide pins 94a and 94b, among the two side surfaces of the bottom plate portion 91 intersecting the x-direction. Each guide pin 94a, 94b extends along the y-direction and protrudes from the upper surface 91a. The tip of each guide pin 94a, 94b is spherical. The shape of each guide pin 94a, 94b in a cross-section perpendicular to its extending direction is, for example, circular.

[0068] The side walls 92a, 92b and the back wall 92c are formed integrally with each other. The bottom plate 91 and the vertical wall 92 may be formed integrally with each other or individually. The material of the bottom plate 91 is, for example, a metal such as cobalt, or glass. The material of the vertical wall 92 is, for example, a metal such as cobalt. When the bottom plate 91 and the vertical wall 92 are formed individually, the materials of the bottom plate 91 and the vertical wall 92 may be different. In this case, the material of the bottom plate 91 is, for example, glass, and the material of the vertical wall 92 is, for example, a metal such as cobalt.

[0069] The lens array 5D has, in addition to the configuration of the lens array 5 of the embodiment described above, a pair of guide holes 58c and 58d. The guide hole 58c is formed near the side surface 5e of the lens array 5D. The guide hole 58d is formed near the side surface 5f of the lens array 5D. Each guide hole 58c and 58d penetrates the lens array 5D along the y-direction from the top surface 5c to the bottom surface 5b. Each guide hole 58c and 58d does not have to penetrate the lens array 5D. The shape of each guide hole 58c and 58d in a cross-section perpendicular to the direction of extension is, for example, circular.

[0070] The guide pins 94a, 94b and guide holes 58c, 58d constitute a third positioning structure C3A that determines the positional relationship between the lens array 5D and the optical integrated circuit 7. The guide pin 94a of the receptacle 9 is inserted into the guide hole 58c of the lens array 5D. The guide pin 94b of the receptacle 9 is inserted into the guide hole 58d of the lens array 5D.

[0071] As shown in this modified example, the optical coupling component 10A may include a receptacle 9 and a third positioning structure C3A. The receptacle 9 is fixed to the optical integrated circuit 7 and connected to the lens array 5D. The third positioning structure C3A includes guide holes 58c and 58d provided in the lens array 5D, and guide pins 94a and 94b provided in the receptacle 9. The positional relationship between the lens array 5D and the optical integrated circuit 7 is determined by inserting the guide pin 94a into the guide hole 58c and the guide pin 94b into the guide hole 58d. In this case, the lens array 5D and the optical integrated circuit 7 can be aligned with high precision. Therefore, the optical coupling efficiency can be improved.

[0072] As shown in this modified example, the difference in the coefficient of linear expansion between the receptacle 9 and the optical integrated circuit 7 is 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array 5D and the optical integrated circuit 7 can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved. [Seventh Modification]

[0073] Figure 20 is a perspective view showing the appearance of receptacle 9A as a modified example of receptacle 9. Figure 21 is a perspective view showing the appearance of main body 3E as a modified example of main body 3. Figure 22 is a side view showing the appearance of main body 3E as a modified example of main body 3. In this modified example, the optical coupling component 10A includes receptacle 9A instead of receptacle 9 of the modified example. Receptacle 9A has a pair of guide holes 95a and 95b instead of the pair of guide pins 94a and 94b of the modified example. Guide hole 95a is provided between side wall portion 92a and side wall portion 92b, at a position closer to side wall portion 92a of the bottom plate portion 91. Guide hole 95b is provided between side wall portion 92a and side wall portion 92b, at a position closer to side wall portion 92b of the bottom plate portion 91. Each guide hole 95a, 95b penetrates the bottom plate portion 91 along the y-direction. Each guide hole 95a, 95b does not necessarily have to penetrate the bottom plate portion 91. The shape of each guide hole 95a, 95b in a cross-section perpendicular to its extending direction is, for example, circular.

[0074] In this modified example, the optical coupling component 10A includes a main body 3E instead of the main body 3D of the above modified example. The main body 3E has a lens array 5E instead of the lens array 5. The lens array 5E has a pair of guide pins 59a and 59b instead of a pair of guide holes 58c and 58d. Guide pin 59a is provided on the bottom surface 5b of the lens array 5E, closer to the side surface 5e. Guide pin 59b is provided on the bottom surface 5b of the lens array 5E, closer to the side surface 5f. Each guide pin 59a and 59b extends along the y-direction and protrudes from the bottom surface 5b. The tip of each guide pin 59a and 59b is spherical. The shape of each guide pin 59a and 59b in a cross-section perpendicular to the direction of extension is, for example, circular.

[0075] In this modified example, the optical coupling component 10A includes a third positioning structure C3B instead of the third positioning structure C3A of the above modified example. The guide pins 59a, 59b and guide holes 95a, 95b constitute the third positioning structure C3B that determines the positional relationship between the lens array 5E and the optical integrated circuit 7. The guide pin 59a of the lens array 5E is inserted into the guide hole 95a of the receptacle 9A. The guide pin 59b of the lens array 5E is inserted into the guide hole 95b of the receptacle 9A.

[0076] As shown in this modified example, the optical coupling component 10A may include a receptacle 9A and a third positioning structure C3B. The receptacle 9A is fixed to the optical integrated circuit 7 and connected to the lens array 5E. The third positioning structure C3B includes guide holes 95a and 95b provided in the receptacle 9A, and guide pins 59a and 59b provided in the lens array 5E. The positional relationship between the lens array 5E and the optical integrated circuit 7 is determined by inserting the guide pin 59a into the guide hole 95a and the guide pin 59b into the guide hole 95b. In this case, the lens array 5E and the optical integrated circuit 7 can be aligned with high precision. Therefore, the optical coupling efficiency can be improved.

[0077] In this modified example as well, the difference in the coefficient of linear expansion between the receptacle 9A and the optical integrated circuit 7 is 20 × 10 －６ The temperature may be below [ / °C]. In this case, the accuracy of the alignment between the lens array 5E and the optical integrated circuit 7 can be prevented from decreasing due to thermal effects in the operating environment. Therefore, the optical coupling efficiency can be improved.

[0078] The optical coupling component according to this disclosure is not limited to the embodiments and variations described above, and various other modifications are possible. For example, although the above embodiments illustrate a case where the optical fiber holding component and lens array are made of resin, the constituent materials of the optical fiber holding component and lens array are not limited to resin. Also, although the above embodiments illustrate a configuration in which the optical fiber holding component and lens array are directly connected, the optical fiber holding component and lens array may be indirectly connected through another member (for example, an optical integrated circuit 7).

[0079] 1...Electronic circuit module 2...Electronic circuit board 3, 3A, 3B, 3C, 3D, 3E...Main body 4, 4A, 4B, 4C...Optical fiber holding component 4a, 5d...Front end surface 4b, 5b...Bottom surface 4c, 5c...Top surface 4d, 5a...Rear end surface 4e, 4f, 5e, 5f...Side surface 5, 5A, 5B, 5C, 5D, 5E...Lens array 6...Tape fiber 7...Optical integrated circuit 8...Guide pin 9, 9A...Receptacle 10, 10A...Optical coupling component 21...Wiring board 22...Large-scale integrated circuit element 41...Fiber hole 42...Single fiber hole 43...Recess 44a, 44b...Guide groove 45a, 45b...Guide hole 51...Spatial structure 52...Optical reflective surface 52a...Concave surface 53...Lens mirror 54...Metal film 55...Increased reflectivity film 56...Protrusion 57a, 57b...Guide groove 58a, 58b, 58c, 58d...Guide hole 59a, 59b...Guide pin 61...Optical fiber 62...Resin coating 91...Bottom plate 91a...Top surface 92...Vertical wall 92a, 92b...Side wall 92c...Back wall 93...Opening 94a, 94b...Guide pin 95a, 95b...Guide hole C1...First positioning structure C2A, C2B...Second positioning structure C3A, C3B...Third positioning structure L...Optical path

Claims

1. An optical coupling component for optically coupling a plurality of optical fibers and an optical integrated circuit, comprising: the plurality of optical fibers; an optical fiber holding component for holding the plurality of optical fibers; and a lens array having a plurality of lens mirrors, wherein each of the plurality of lens mirrors changes the angle of the optical path between each of the plurality of optical fibers and the optical integrated circuit; the lens array has a spatial structure in which the portion of the optical path that enters the lens array and exits the lens array passes through air; and the optical fiber holding component and the lens array are formed independently of each other and are connected to each other directly or indirectly.

2. The optical coupling component according to claim 1, wherein the optical fiber holding component has a plurality of fiber holes, each of the plurality of fiber holes fixes each of the plurality of optical fibers inserted into each of the plurality of fiber holes, and the tip surface of each of the plurality of optical fibers is flush with one end surface of the optical fiber holding component.

3. The optical coupling component according to claim 1 or 2, wherein the optical fiber holding component and the lens array are made of resin.

4. The optical coupling component according to any one of claims 1 to 3, wherein each of the plurality of lens mirrors has a metal film provided on at least a portion of the surface of the lens array.

5. The optical coupling component according to any one of claims 1 to 4, wherein each of the plurality of lens mirrors has an reflective coating provided on at least a portion of the surface of the lens array.

6. The difference in the coefficient of thermal expansion between the optical fiber holding component and the lens array is 50 × 10 －６ The optical coupling component according to any one of claims 1 to 5, wherein the temperature is less than or equal to [ / °C].

7. The difference in the coefficient of thermal expansion between the optical fiber holding component and the lens array is 20 × 10 －６ The optical coupling component according to claim 6, wherein the temperature is below [ / °C].

8. An optical coupling component according to any one of claims 1 to 7, comprising a first positioning structure having a protrusion provided on one of the optical fiber holding component and the lens array, and a recess provided on the other of the optical fiber holding component and the lens array, wherein the positional relationship between the optical fiber holding component and the lens array is determined by inserting the protrusion into the recess.

9. The optical coupling component according to any one of claims 1 to 7, further comprising a second positioning structure that includes guide holes or guide grooves provided in both the optical fiber holding component and the lens array, and determines the positional relationship between the optical fiber holding component and the lens array by inserting a positioning component into the guide holes or pressing the positioning component into the guide grooves.

10. The optical integrated circuit further comprises the lens array and the optical integrated circuit, wherein the difference in the coefficient of thermal expansion between the lens array and the optical integrated circuit is 50 × 10 －６ The optical coupling component according to any one of claims 1 to 9, wherein the temperature is below [ / °C].

11. The difference in the coefficient of thermal expansion between the lens array and the optical integrated circuit is 20 × 10 －６ The optical coupling component according to claim 10, wherein the temperature is below [ / °C].

12. The optical coupling component according to any one of claims 1 to 9, further comprising the optical integrated circuit, wherein the optical fiber holding component is bonded to the lens array, and either the optical fiber holding component or the lens array or both are bonded to the optical integrated circuit.

13. The optical coupling component according to any one of claims 1 to 12, further comprising: a connecting portion fixed to the optical integrated circuit and connected to the lens array; a guide hole provided in one of the connecting portion and the lens array; and a guide pin provided in the other of the connecting portion and the lens array, wherein the positional relationship between the lens array and the optical integrated circuit is determined by inserting the guide pin into the guide hole.

14. The difference in the coefficient of linear expansion between the connection portion and the optical integrated circuit is 20 × 10 －６ The optical coupling component according to claim 13, wherein the temperature is below [ / °C].

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