TW201830071A - Optical waveguide member and optical coupling structure - Google Patents

Abstract

Disclosed is an optical waveguide member that brings together and connects: a first optical waveguide component that has a plurality of light entry/exit parts; and a second optical waveguide component that has a plurality of light entry/exit parts. The optical waveguide member comprises: a main body part that has first and second end surfaces; and a plurality of optical waveguides that extend inside the main body part from the first end surface to the second end surface. First ends of the plurality of optical waveguides are exposed at the first end surface in a one-dimensional array, and second ends of the plurality of optical waveguides are exposed at the second end surface in a two-dimensional array. The mode field diameter of the first end of each optical waveguide is different from the mode field diameter of the second end of each optical waveguide.

Description

Optical waveguide member and optical coupling structure

The present invention relates to an optical waveguide member and an optical coupling structure. The present application claims priority on Japanese Patent Application No. Hei. No. Hei. No. Hei.

Non-Patent Document 1 discloses a fan-out part in which a PC (Physical Contact) is connected to an LC (Lucent Connector) connector type multi-core fiber (MCF: Multi Core Fiber). In the fan-out part, a bundle of a plurality of single-core fibers is bundled to form a bundle. In the front end portion, the cores of the plurality of single-core fibers are arranged two-dimensionally when viewed from the optical axis direction, and the core of the MCF is also arranged two-dimensionally when viewed from the optical axis direction. The core of a plurality of single-core fibers and the core of the MCF oppose each other. Non-Patent Document 2 discloses a Mode-Field-Converting Fiber (MFC fiber). The MFC fiber is disposed between the optical waveguide wafer and the optical fiber having mutually different mode field shapes and sizes. One end of the MFC fiber is butt-connected to the optical fiber, and the other end of the MFC fiber is butted to the optical waveguide chip. The MFC fiber has a tapered portion formed by heat treatment. In the taper portion, the shape and size of the mode field of the MFC fiber are converted in the following manner: the shape and size of the mode field at one end of the MFC fiber are respectively integrated into the shape and size of the mode field of each fiber, and the other end of the MFC fiber is used. The shape and size of the mode field are integrated into the shape and size of the mode field of the optical waveguide chip. [Non-patent literature] [Non-Patent Document 1] Kawashima Sho, and other two "LC connector type multi-core fiber fan-out", 2015 Electronic Information and Communication Society Communications Association Conference Communication Lecture Collection, Society Corporate Electronic Information and Communication Society, B-13-34, August 25, 2015 [Non-Patent Document 2] Yanagawa Kyuji "Mode Field Conversion Fiber", Optics, Japan Optics Association, Vol. 24, No. 5, 284-285 Page, May 1995

The optical waveguide member of the present invention is connected to a first optical waveguide component having a plurality of light incident and output portions and a second optical waveguide component having a plurality of light incident and output portions. The optical waveguide member includes a main body portion having first and second end faces, and a plurality of optical waveguides extending from the first end surface to the second end surface in the main body portion. The first ends of the plurality of optical waveguides are arranged in a one-dimensional shape and are exposed to the first end faces, and the second ends of the plurality of optical waveguides are arranged two-dimensionally and are exposed to the second end faces. The mode field diameter of the first end of each optical waveguide is different from the mode field diameter of the second end of each optical waveguide.

[Problems to be Solved by the Invention] In the method of connecting two optical waveguide components (fiber bundles and MFCs) described in Non-Patent Document 1, the core arrangement of each optical waveguide component is restricted. The reason for this is that each of the cores is disposed so that the optical fiber bundle, which is an optical waveguide component, can be viewed from the optical axis direction, and the plurality of single-core optical fibers have the highest density (the densest arrangement). Therefore, in this mode, when the core configuration of one optical waveguide component is different from the core configuration of another optical waveguide component, for example, the core of the optical waveguide component is configured as one-dimensional, and the other optical waveguide component is When the core configuration is two-dimensional, it is difficult to connect them. In the aspect described in Non-Patent Document 2, the taper portion formed by the heat treatment is provided on the MFC fiber, thereby connecting the optical waveguide wafer and the optical fiber in which the shape and size of the mode field are different from each other. However, in order to form such a tapered portion on an MFC optical fiber, it is necessary to ensure the length of the MFC optical fiber to some extent. As a result, the MFC fiber is elongated and the device is enlarged. [Effects of the Invention] According to the present disclosure, when optical waveguide components having a plurality of light incident and exit portions are connected to each other, even if a plurality of light incident and exit portions of one optical waveguide component are arranged in a one-dimensional manner, they are arranged two-dimensionally. In the case where a plurality of light of the other optical waveguide component is incident on the exit portion, and the mode field diameter of the light incident exit portion of one optical waveguide component is different from the mode field diameter of the light incident exit portion of the other optical waveguide component They can also be preferably connected. [Description of Embodiments of the Present Invention] First, the contents of the embodiments of the present invention will be listed. The optical waveguide member according to the embodiment of the present invention is connected to a first optical waveguide component having a plurality of light incident and output portions and a second optical waveguide component having a plurality of light incident and output portions. The optical waveguide member includes a main body portion having first and second end faces, and a plurality of optical waveguides extending from the first end surface to the second end surface in the main body portion. The first ends of the plurality of optical waveguides are arranged in a one-dimensional shape and are exposed to the first end faces, and the second ends of the plurality of optical waveguides are arranged in a two-dimensional manner and exposed to the second end faces. The mode field diameter of the first end of each optical waveguide is different from the mode field diameter of the second end of each optical waveguide. In the above optical waveguide member, the first ends of the optical waveguides are arranged in a one-dimensional manner, and the second ends are arranged in two dimensions. Therefore, even when the arrangement of the light incident and exit portions of the first optical waveguide component is arranged one-dimensionally, and the arrangement of the light incident and exit portions of the second optical waveguide component is two-dimensionally arranged, The light incident exit portions are optically coupled to each other. Further, since the mode field diameter of the first end of each optical waveguide and the mode field diameter of the second end are different from each other, the mode field diameters of the light incident and exit portions of the first and second optical waveguide components are different from each other. In the case, it is also possible to connect them efficiently. Therefore, when the first and second optical waveguide components are connected, the light-transmitting and emitting portions of the first optical waveguide component are arranged in a one-dimensional manner, and the second optical waveguide component is two-dimensionally arranged. When the respective light beams are incident on the emitting portion, and the mode field diameters of the light incident and the emitting portions are different from each other, they may be preferably connected. The above configuration of the optical waveguide of the optical waveguide member can be preferably formed using an ultrashort pulse laser such as a femtosecond laser. In the above optical waveguide member, the first end surface and the second end surface face each other, and the distance between the first end surface and the second end surface may be the width of the first end surface of the plurality of optical waveguides arranged in the first end surface. 80 times or less. In this manner, the optical waveguide member can be downsized by reducing the distance between the first end surface and the second end surface. Thereby, the miniaturization of the optical module including the optical waveguide member can be achieved. In the above optical waveguide member, the body portion and the plurality of optical waveguides may be composed of quartz glass. Thereby, a plurality of optical waveguides of the optical waveguide member can be preferably realized using, for example, the above-described pulsed laser. In the above optical waveguide member, the main body portion and the plurality of optical waveguides may be composed of quartz glass to which at least one refractive index adjusting material selected from the group consisting of potassium, germanium, fluorine, boron, and phosphorus is added. Thereby, since the refractive index of each optical waveguide can be changed with good efficiency using, for example, the above-described pulse laser, a plurality of optical waveguides of the optical waveguide member can be preferably realized. In the above optical waveguide member, each optical waveguide may further have a mode field converting portion, and in each of the mode field converting portions, the mode field diameter may be 17 μm/mm or less from the size of the first end to the second end. Change rate changes. By providing such a mode field converting portion to each of the optical waveguides, it is possible to suppress a sudden change in the mode field diameter of each of the optical waveguides, thereby suppressing generation of light leakage from the respective optical waveguides. In the above optical waveguide member, the mode end diameter of the first end of the plurality of optical waveguides may be 3 μm or more and 5 μm or less, and the mode end diameter of the second end of the plurality of optical waveguides may be 5 μm or more and 20 μm. the following. The mode field diameter of the second end of the plurality of optical waveguides may be larger than the mode field diameter of the first end of the plurality of optical waveguides. The optical axis of the first end of the plurality of optical waveguides may be offset by an angle of 10° or less with respect to a normal direction of the first end surface, and the optical axis of the second end of the plurality of optical waveguides may be opposite to the second end surface The line direction is offset by an angle of 10° or less. When each of the plurality of optical waveguides is viewed from a direction orthogonal to the opposing direction of the first and second end faces, at least a portion of the optical waveguides may intersect with the other optical waveguides. The main body portion may have a substantially rectangular parallelepiped shape defined by the first and second end faces, the upper surface and the lower surface facing each other, and the first and second side faces opposed to each other, and the distance between the upper surface and the lower surface may be 80 μm or more and 1000 μm or less, and the distance between the first and second sides may be 80 μm or more and 1000 μm or less. The optical coupling structure according to the embodiment of the present invention includes the optical waveguide member having the above-described configuration, and the first optical waveguide component disposed on the first end surface side of the optical waveguide member or disposed on the second end surface side of the optical waveguide member At least one of the second optical waveguide components. The first optical waveguide component has a plurality of light incident and output portions arranged in a one-dimensional manner, and is optically coupled to each other by the first end of the optical waveguide member and the light incident and output portions of the first optical waveguide component. It is connected to the optical waveguide member. The second optical waveguide component has a plurality of light incident and output portions that are two-dimensionally arranged, and are optically coupled to each other by the second end of the optical waveguide member and the light incident and output portions of the second optical waveguide component. It is connected to the optical waveguide member. In this case, similarly to the above-described optical waveguide member, it is preferable to dispose the first optical waveguide component in which the light incident and the output portions are arranged in one dimension, and the mode field diameter and the first optical waveguide component are different. The configuration in which the second optical waveguide components of the respective light incident and output portions are connected in a continuous manner is connected. In the above optical coupling structure, the first optical waveguide component may be a germanium photonic wafer. The second optical waveguide component may be a multi-core optical fiber having a plurality of cores and a sheath covering the plurality of cores. Further, the optical coupling structure described above may be configured to include both the first optical waveguide component and the second optical waveguide component. [Details of Embodiments of the Present Invention] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The invention is not limited to the exemplified embodiments, but is intended to cover all modifications within the scope and scope of the invention. In the following description, the same elements are denoted by the same reference numerals in the description of the drawings, and the description thereof will not be repeated. Fig. 1 is a perspective view of an optical waveguide member 1 of the present embodiment. The XYZ orthogonal coordinate system is shown in Figure 1 for ease of understanding. As shown in FIG. 1, the optical waveguide member 1 includes a main body portion 10 and a plurality of optical waveguides 20. The body portion 10 has an appearance of a substantially rectangular parallelepiped shape. A plurality of optical waveguides 20 are disposed in the body portion 10. The body portion 10 and the plurality of optical waveguides 20 are made of the same material. The main body portion 10 and the plurality of optical waveguides 20 are made of, for example, quartz glass. Or the body portion 10 and the plurality of optical waveguides 20 may be adjusted by adding at least one refractive index selected from the group consisting of potassium (K), germanium (Ge), fluorine (F), boron (B), and phosphorus (P), for example. It is composed of quartz glass with an additive (refractive index adjusting material). In this case, the additive may be added throughout the main body portion 10 and the plurality of optical waveguides 20, or may be added to a portion of the main body portion 10 including the plurality of optical waveguides 20. The main body portion 10 has an end surface 10a, an end surface 10b, an upper surface 10c, a lower surface 10d, a side surface 10e, and a side surface 10f. The end surface 10a and the end surface 10b are disposed opposite to each other in the Z direction. In one example, the end faces 10a and 10b are flat faces and are parallel to each other. The upper surface 10c and the lower surface 10d are disposed opposite to each other in the Y direction and extend in the Z direction. In one example, the upper surface 10c and the lower surface 10d are flat surfaces and are parallel to each other. The side surface 10e and the side surface 10f are disposed opposite to each other in the X direction and extend in the Z direction. In one example, the side faces 10e and 10f are flat faces and are parallel to each other. The distance between the end surface 10a and the end surface 10b is 1 mm or more and 80 times or less the width of the end surface 10a of the plurality of optical waveguides 20 in the array direction of the end surface 10a, which is 5 mm in one embodiment. The distance between the upper surface 10c and the lower surface 10d and the distance between the side surface 10e and the side surface 10f are 80 μm or more and 1000 μm or less, which is 125 μm in one embodiment. When the distance between the end surface 10a and the end surface 10b is 10 mm or less, the distance between the upper surface 10c and the lower surface 10d, and the distance between the side surface 10e and the side surface 10f are 125 μm, respectively, the volume of the main body portion 10 is 0.16 mm ³ or less. A plurality of optical waveguides 20 extend from the end face 10a to the end face 10b. One end surface (one end) 20a of the plurality of optical waveguides 20 is included in the end surface 10a, and the other end surface (the other end) 20b of the plurality of optical waveguides 20 is included in the end surface 10b. The end surface 20a and the other end surface 20b are different from the refractive indices of the light-emitting portions 31 and 41 (see FIG. 4 described later) and the one end surface 20a and the other end surface 20b of the optical waveguide components 30 and 40 to be connected. The intermediate light is respectively refracted, so that the optical axis direction of each end face 20a and the normal direction of the end face 10a do not necessarily coincide with each other. That is, the optical axis of one end face 20a of the plurality of optical waveguides 20 can be shifted with respect to the normal direction of the end face 10a, and the offset amount is preferably 10 or less. Similarly, the optical axis direction of each of the other end faces 20b and the normal direction of the end faces 10b do not necessarily coincide with each other. That is, the optical axis of the other end surface 20b of the plurality of optical waveguides 20 can be shifted with respect to the normal direction of the end surface 10b, and the offset amount is preferably 10 or less. The mode field diameter of each of the other end faces 20b of the end faces 10b and the mode field diameter of each end face 20a of the end faces 10a are different from each other. Here, FIG. 2 is a front view showing the end face 10a of the optical waveguide member 1. As shown in FIG. 2, in one embodiment, the plurality of one end faces 20a have a circular shape, and the shape of the mode field is also a circular shape. The mode field diameter of the plurality of one end faces 20a is, for example, 3 μm or more and 5 μm or less. Each of the plurality of one end faces 20a is exposed at a position corresponding to the arrangement of the light incident/emitting portion 31 (see FIG. 4) of the optical waveguide component 30 to be described later. Specifically, a plurality of one end faces 20a of the end face 10a are arranged in a one-dimensional shape. In one embodiment, the four end faces 20a are equally spaced along the X direction and arranged in a row. Fig. 3 is a rear view showing the end face 10b of the optical waveguide member 1. As shown in FIG. 3, in one embodiment, the plurality of other end faces 20b have a circular shape, and the shape of the mode field is also a circular shape. The mode field diameter of the plurality of other end faces 20b is, for example, 5 μm or more and 20 μm or less, and is larger than the mode field diameter of the plurality of one end faces 20a. Each of the plurality of other end faces 20b is exposed at a position corresponding to the arrangement of the light incident/emitting portion 41 (see FIG. 4) of the optical waveguide component 40 to be described later. Specifically, the plurality of other end faces 20b of the end face 10b are two-dimensionally arranged. In one embodiment, the two other end faces 20b arranged along the X direction are arranged across the Y direction and in two rows. In the optical waveguide 20, when the arrangement is changed from the one-dimensional arrangement to the two-dimensional arrangement, when viewed from the Y direction orthogonal to the opposite direction (Z direction) of the end faces 10a and 10b, At least a portion of the optical waveguide 20 intersects with other optical waveguides (see FIG. 4). Referring again to Figure 1. Each optical waveguide 20 includes a mode field converting portion 20c that changes the mode field diameter of each optical waveguide 20 between the end surface 10a and the end surface 10b. In one embodiment, as shown in FIG. 1, the entire range of the optical waveguides 20 from the end faces 10a to 10b is the mode field converting portion 20c. The mode field converting portion 20c can be partially formed in the range from the end surface 10a to the end surface 10b. In the mode field converting portion 20c, the mode field diameter is changed from the size of each end surface 20a to the size of each of the other end faces 20b (for example, a rate of change of 17 μm/mm or less). In other words, the mode field diameter of each optical waveguide 20 is changed in such a manner that the mode field diameter of each end face 20a gradually approaches the mode field diameter of each of the other end faces 20b as approaching the end face 10b. The plurality of optical waveguides 20 having such a configuration are formed in the body portion 10 by laser processing such as pulsed laser. The pulsed laser is, for example, a Ti-sapphire Femtosecond Laser. When the condensed spot of the light pulse output from the pulsed laser is formed in the body portion 10, the refractive index of the body portion 10 changes at the condensing point. Therefore, by scanning the condensed spot, a plurality of three-dimensional optical waveguides 20 having a trajectory not only in the X direction but also in the Y direction are formed in the body portion 10. Here, when both the main body portion 10 and the plurality of optical waveguides 20 are made of quartz glass to which the above-mentioned additive material is added, the refractive index of the main body portion 10 of the light collecting point of the light pulse changes depending on the additive material. The status is different. For example, in the case where the additive is potassium, barium, or phosphorus, the refractive index of the light spot is higher than the refractive index around it. Therefore, in this case, a plurality of optical waveguides 20 (core regions) are formed along the trajectory of the light collecting point of the light pulse. Further, depending on the additives, the amount of change in the refractive index of the light collecting point of the light pulse is different. On the other hand, for example, when the additive is fluorine or boron, the refractive index of the light-converging point is lower than the refractive index around it. Therefore, in this case, the periphery (the shell region) of the plurality of optical waveguides 20 is formed along the trajectory of the light collecting point of the light pulse. Further, depending on the type of the additives, the amount of change in the refractive index of the light collecting point of the light pulse is different. 4 is a plan view showing a state in which the optical waveguide components 30 and 40 are connected to each other via the optical waveguide member 1 of the present embodiment. Moreover, the XZ coordinate system shown in FIG. 4 corresponds to the XYZ orthogonal coordinate system shown in FIG. As shown in FIG. 4, the optical waveguide member 1 is disposed between the optical waveguide component 30 and the optical waveguide component 40, and is butt-connected to the optical waveguide components 30, 40 in the Z direction. An optical coupling structure is formed by at least one of the optical waveguide member 1 and the waveguide component 30 or the optical waveguide component 40. The optical waveguide component 30 is the first optical waveguide component of the present embodiment, and is, for example, a silicon photonics chip. The optical waveguide component 30 has a connection end face 30a and a plurality of light incident and exit sections 31. The connecting end face 30a is opposed to the end face 10a, and in one embodiment is PC-connected to the end face 10a. The plurality of light incident/emitting portions 31 are end faces of the optical waveguide extending in the Z direction from the connection end surface 30a, and are arranged one-dimensionally along the X direction. The plurality of light incident and output portions 31 are optically coupled to the plurality of one end faces 20a, respectively. The mode field diameter of each of the light incident and exit portions 31 is integrated (consistent) with the mode field diameter of each of the end faces 20a. In one embodiment, each light incident and exit portion 31 has a circular shape, and the mode field has a circular shape. The optical waveguide component 40 is a second optical waveguide component of the present embodiment, and is, for example, a multi-core optical fiber having a plurality of cores and a fiber case covering the plurality of cores. The optical waveguide component 40 has a connection end surface 40a and a plurality of light incident and exit portions 41. The connecting end face 40a is opposed to the end face 10b, and in one embodiment is PC-connected to the end face 10b. The plurality of light incident/emitting portions 41 are end faces of the plurality of cores extending from the connection end surface 40a in the Z direction, and are optically coupled to the plurality of other end faces 20b, respectively. The mode field diameter of each of the light incident exit portions 41 is integrated (consistent) with the mode field diameter of each of the other end faces 20b. In one embodiment, each light incident and exit portion 41 has a circular shape, and the mode field has a circular shape. In the optical waveguide member 1 of the present embodiment, light emitted from each of the light incident and output portions 31 of the optical waveguide component 30 is incident on one end surface 20a of each optical waveguide 20, and is emitted from the other end surface 20b of each optical waveguide 20, respectively. And each of the light incident on the optical waveguide component 40 is incident on the exit portion 41. Further, the light emitted from each of the light incident and output portions 41 is incident on the other end surface 20b of each of the optical waveguides 20, and is emitted from one end surface 10a of each of the optical waveguides 20, and is incident on each of the light incident/emission portions 31. The effect obtained by the optical waveguide member 1 of the present embodiment described above will be described. As shown in FIGS. 1 to 3, one end surface 20a of each optical waveguide 20 is arranged in one-dimensional shape, and the other end surface 20b is arranged in two dimensions. Therefore, even if the arrangement of the light incident/emitting portions 31 is one-dimensionally arranged as viewed from the optical axis direction of the light incident and output portion 31, for example, the arrangement of the respective light incident and output portions 41 is, for example, In the case where the optical fibers are arranged two-dimensionally when viewed from the optical axis direction of the light incident/emitting portion 41, the respective light incident and output portions 31 and 41 may be optically coupled to each other. Further, unlike the configuration described in Non-Patent Document 1, the arrangement of one end surface 20a and the other end surface 20b of the optical waveguide 20 can be freely designed. Therefore, the degree of freedom in arrangement of the respective light incident and output portions 31, 41 can be improved. Further, since the mode field diameter of each of the end faces 20a and the mode field diameter of each of the other end faces 20b are different from each other, the mode field diameter of each of the light incident and exit portions 31 and the mode field of each of the light incident and exit portions 41 are When the diameters are different from each other, these may be connected efficiently. Therefore, in the optical waveguide member 1 of the present embodiment, when the optical waveguide component 30 and the optical waveguide component 40 are connected, even if the light incident/emission portions 31 are arranged in a one-dimensional manner, the respective light incident and exit portions 41 are arranged two-dimensionally. In the case where the mode field diameters of the respective light incident and output portions 31 and 41 are different from each other, the degree of freedom in arrangement of the light incident and output portions 31 and 41 can be increased, and the light can be preferably connected. As in the present embodiment, the distance between the end surface 10a and the end surface 10b may be 80 times or less the width of the end surface 10a of the plurality of optical waveguides 20 in the array direction of the end surface 10a. Thus, the optical waveguide member 1 can be miniaturized by reducing the distance between the end surface 10a and the end surface 10b. Thereby, the miniaturization of the optical module including the optical waveguide member 1 can be achieved. As in the present embodiment, the main body portion 10 and the plurality of optical waveguides 20 can be made of quartz glass. Thereby, the plurality of optical waveguides 20 of the optical waveguide member 1 can be preferably realized using the above-described pulsed laser. As in the present embodiment, the main body portion 10 and the plurality of optical waveguides 20 may be made of quartz glass to which at least one additive selected from the group consisting of potassium, barium, fluorine, boron, and phosphorus is added. Thereby, since the refractive index of each optical waveguide 20 can be changed efficiently using the pulse laser described above, the plurality of optical waveguides 20 of the optical waveguide member 1 can be preferably realized. As in the present embodiment, each of the optical waveguides 20 may further have a mode field converting portion 20c. By providing such a mode field converting portion 20c to each of the optical waveguides 20, it is possible to suppress a sudden change in the mode field diameter of each of the optical waveguides 20, thereby suppressing light leakage from the optical waveguides 20 and reducing connection loss.

1‧‧‧ Optical waveguide components

2c‧‧•Mode Field Conversion Department

10‧‧‧ Body Department

10a‧‧‧ end face

10b‧‧‧ end face

10c‧‧‧ upper surface

10d‧‧‧lower surface

10e‧‧‧ side

10f‧‧‧ side

20‧‧‧ Optical Waveguide

20a‧‧‧One end

20b‧‧‧Other end face

30‧‧‧ Optical waveguide parts

30a‧‧‧connection end face

31‧‧‧Light incident exit

40‧‧‧ Optical waveguide parts

40a‧‧‧connection end face

41‧‧‧Light incident exit

X‧‧‧ direction

Y‧‧‧ direction

Z‧‧‧ direction

Fig. 1 is a perspective view of an optical waveguide member of an embodiment. Fig. 2 is a front elevational view showing one end face of the optical waveguide member shown in Fig. 1. Fig. 3 is a rear elevational view showing the other end face of the optical waveguide member shown in Fig. 1. 4 is a plan view showing a state (optical coupling structure) in which optical waveguide components are connected to each other via an optical waveguide member according to an embodiment.

Claims (15)

An optical waveguide member that is butt-joined to a first optical waveguide component having a plurality of light incident and output portions and a second optical waveguide component having a plurality of light incident and output portions, and includes: a main body portion having a first And the second end surface; and the plurality of optical waveguides extending from the first end surface to the second end surface in the main body portion; and the first ends of the plurality of optical waveguides are arranged in a one-dimensional manner and are respectively exposed to the first end The second end of the plurality of optical waveguides is arranged two-dimensionally and exposed to the second end surface, and a mode field diameter of the first end of each optical waveguide and a mode field of the second end of each optical waveguide The diameters are different from each other. The optical waveguide member according to claim 1, wherein the first end surface and the second end surface face each other, and a distance between the first end surface and the second end surface is an arrangement direction of the plurality of optical waveguides of the first end surface The width of the first end surface is 80 times or less. The optical waveguide member according to claim 1 or 2, wherein the main body portion and the plurality of optical waveguides are made of quartz glass. The optical waveguide member according to claim 1 or 2, wherein the main body portion and the plurality of optical waveguides are made of quartz glass to which at least one refractive index adjusting material selected from the group consisting of potassium, germanium, fluorine, boron, and phosphorus is added. Composition. The optical waveguide member according to any one of claims 1 to 4, wherein each of the optical waveguides further has a mode field converting portion, and in each of the mode field converting portions, a mode field diameter is from a size of the first end to a second end The size varies with a rate of change of 17 μm/mm or less. The optical waveguide member according to any one of claims 1 to 5, wherein a mode field diameter of the first end of the plurality of optical waveguides is 3 μm or more and 5 μm or less. The optical waveguide member according to any one of claims 1 to 6, wherein a mode field diameter of the second end of the plurality of optical waveguides is 5 μm or more and 20 μm or less. The optical waveguide member according to any one of claims 1 to 7, wherein a mode field diameter of said second end of said plurality of optical waveguides is larger than a mode field diameter of said first end of said plurality of optical waveguides. The optical waveguide member according to any one of claims 1 to 8, wherein an optical axis of the first end of the plurality of optical waveguides is shifted by an angle of 10 or less with respect to a normal direction of the first end surface. The optical waveguide member according to any one of claims 1 to 9, wherein an optical axis of the second end of the plurality of optical waveguides is shifted by an angle of 10 or less with respect to a normal direction of the second end surface. The optical waveguide member according to any one of claims 1 to 10, wherein each of the plurality of optical waveguides is at least partially and other when viewed from a direction orthogonal to a direction opposite to the first and second end faces The waveguide crosses. The optical waveguide member according to any one of claims 1 to 11, wherein the main body portion has the first and second end faces, the upper surface and the lower surface facing each other, and the first and second sides facing each other The substantially rectangular parallelepiped shape defined by the distance between the upper surface and the lower surface is 80 μm or more and 1000 μm or less, and the distance between the first and second side surfaces is 80 μm or more and 1000 μm or less. An optical coupling structure comprising: the optical waveguide member according to any one of claims 1 to 12; and a first optical waveguide component disposed on the first end surface side of the optical waveguide member or disposed on the optical waveguide member At least one of the second optical waveguide component of the second end face side, wherein the first optical waveguide component has a plurality of light incident and output portions arranged in a one-dimensional manner, and each of the first ends of the optical waveguide member The optical waveguide member is butted and optically coupled to each of the light incident and output portions of the first optical waveguide component, and the second optical waveguide component has a plurality of light incident and output portions arranged in two dimensions. And the optical waveguide member is butted to be connected to each other in such a manner that each of the second ends of the optical waveguide member and the light incident/emitting portion of the second optical waveguide component are optically coupled to each other. The optical coupling structure of claim 13, wherein the first optical waveguide component is a germanium photonic wafer. The optical coupling structure of claim 13 or 14, wherein said second optical waveguide component is a multi-core optical fiber having a plurality of cores and a sheath encasing said plurality of cores.